Toyota Drive Shaft Spacers

Contents:

• Introduction
  • How much spacer do I need?
  • Spacer Dimensions
  • Spacer Notes
  • What makes the 4Crawler Offroad spacers different?
• On-line ordering
  • Returns and exchanges
• Installation Instructions
• Contact Info.

Introduction:

On the Toyota 4WD Pickup, 4Runner and Land Cruiser model, the front and rear drive shaft bolt to "companion" flanges on the transfer case with a mating flange on the drive shaft (Propeller Shaft in "Toyota-speak"). On the 2WD pickups, the drive shaft typically slides into a slip yoke output on the transmission and bolts to the rear differential with a flange. Up until now, the only way to make a drive shaft longer was to remove it and have a drive line shop cut the existing tubing off the drive shaft and weld on a new length of tubing. If you needed a significant change in length, this was not so bad to do. But often, you only needed to lengthen the shaft a small amount, from 3/4" to 1-1/2" for example. Since you had pay for a whole new length of drive shaft tubing (plus the labor to install it) and not just the additional inch or so of additional tubing, it could cost hundreds of dollars to have a shaft lengthened, even a short amount. On the other hand, shortening a shaft is typically less expensive, since you can simply separate one end from the shaft tubing, cut the remaining shaft down and re-weld the end back on.

What are some indications that your drive shaft is too short?

• One obvious indication is that the slip yoke on the drive shaft pulls apart as the suspension drops away from the vehicle. This is typical of front drive shafts, especially with a leaf sprung front axle with rear-mounted spring shackles, as is common on solid axle Toyota min-trucks (both factory and solid axle swaps).
• Another less obvious indication is that the slip yoke is not engaged far enough and thus it causes some vibration. An easy way to check for this condition is to grasp the center section of the drive shaft near the slip yoke and give it a good tug side-side. If you feel any play in that slip yoke, you may have too little spline engagement inside (or the slip yoke may be out of grease or even worn out).
• And you may be doing a transmission swap, such as from an automatic to a manual transmission, and that new transmission/transfer case stack length is shorter or longer that it was before. This can cause one of the two drive shafts to be too short.

Ideally, you only want just a little more slip yoke compression travel than needed by the change in drive shaft length as the suspension fully compresses. How much is that? It is hard to give an exact answer, as every vehicle is different. Generally a rear drive shaft needs less slip yoke travel than a front drive shaft. A longer drive shaft generally needs less slip yoke travel than a shorter one. A drive shaft that is at a flatter angle will generally need less travel than one at a steeper angle.

How much spacer do I need?

So how do you determine how much slip yoke travel you need on your vehicle?

• You might be able to see the wear marks on your driveshaft where it used to run before you modified the truck.
  • Ideally, you would have measured your drive shaft angles and lengths prior to modifying your truck so you would know how it was set up from the factory.
    • Lacking those measurements, find a similar model vehicle in stock form and see if you can get a measurement of the drive shaft length.
    • Or, try posting on a vehicle-specific web forum and see if anyone there has either a similar vehicle and modification that has used a driveshaft spacer or has lengthened their shaft and find out what dimension they used. Or lacking that, see if someone with a closer to stock vehicle can measure the shaft length for you.
• You might try driving someplace where you can go over some bumps to get the rear (or front) end to compress fully. Then hop out and examine the cleared portion of the drive shaft slip yoke and mark or measure the amount of compression observed.
  • Often, you can see where the slip yoke is cleaner than the remainder due to the shaft compressing to that point and clearing the old grease and dirt away.
• You could take some careful measurements of the shaft length and height on each end then use that to draw out a triangle, with the shaft on the hypotenuse of the triangle. Then measure how far your suspension can compress from the static ride height and use that to create a new triangle with the shorter height due to the suspension compression. Then solve for the length change of the drive shaft.
  • Here's a really handy Java applet for calculating triangles side lengths and angles.
• Aside from the above, you should probably have 1" to 1-1/2" of rear shaft slip yoke compression length. Up front, you'll probably need 2" or more of slip yoke compression travel, depending on your suspension travel, where the spring shackles are located, etc.

Generally having too much slip yoke compression travel is better than not enough. Whatever you do, you do not want the drive shaft to "bottom out", as that can cause severe damage to the transfer case, as it will take the brunt of the impact should the slip yoke compress fully. But if you have so much slip yoke pull apart that it separates or vibrates is no good either.

There is one situation where a drive shaft spacer may not be an option and that is where a short drive shaft is already running at an extreme angle and/or the joints are near their maximum operating angle. Since installing a spacer effectively shortens the distance between the ends of the shaft (that is how the spacer makes a too short shaft fit), it also will make the angles increase. Normally this is not a big issue on a longer shaft, but on a short shaft where you are already running at the maximum joint angles, the angle change of the spacer may be too much to accommodate. In this case physically lengthening the shaft is the better, albeit more expensive, option.

Until now there has only been one solution, that is to have the shaft physically lengthened at considerable expense. But now available for the Toyota 2WD and 4WD pickup, 4Runner, Tacoma and FJ-series Landcruiser models are some simple bolt-on spacers that fit many of the common drive shaft bolt patterns and typical applications listed below.

Spacer Dimensions:

The spacers are machined from billet T-6061 aluminum and are 107.5mm in diameter (does not need to match the outer diameter of the transfer case or pinion flange exactly) and include 4 - 10mm (or 8mm) metric grade 12.9 mounting bolts and lock nuts to replace the stock mounting bolts. These spacers may fit other Toyota drive shaft flanges and feature a male locating ring on one side (3mm high) and a corresponding female recess (4.5mm deep) on the back side (both approx. 46mm in diameter) to fit the corresponding ring and recess on the stock drive shaft and companion flanges. To check what drive shaft flange bolt hole spacing will work on your truck, measure the center-center bolt hole spacing and compare to the above dimensions and see if you match up with one of the above bolt hole patterns,

When measuring the bolt hole patterns, it might help to imagine a square (or rectangle) formed by the 4 bolt holes in the flange. The corners of the square (or rectangle) will fall upon the center of the bolt holes and it is the width (and length) of that square (or rectangle) that define the bolt hole pattern. For example, if you drew a 60mm x 60mm square then drilled a hole at each corner of that square, you would end up with a 60mm x 60mm bolt hole pattern. This is contrasted to a Bolt Circle Diameter (BCD) measurement which is commonly used on measuring wheel stud locations. For example, a Toyota 6-lug wheel BCD is 6 on 5.5", meaning 6 holes equally spaced around a 5.5" diameter circle. The problem with BCD is that it assumes the bolt holes are equally spaced and while it would work with the square bolt patterns, it does not work for the rectangular patterns as you can't specify where the bolt holes are located along the bolt circle.

Notes:

• The information regarding years vs. bolt hole patterns is typical, but be advised that a previous owner of your vehicle may have swapped in drive line parts from another year vehicle. Also note that this table is by no means to be taken verbatim, that is when we list a given vehicle as using a given pattern, that only means that we have received feedback that a given spacer fit a given vehicle or that we have measured a given bolt pattern on a given vehicle. But if someone purchases a certain spacer and we never hear back, we have no idea what vehicle the spacer was installed on. So about all that can be said is that your vehicle will likely have one (or likely more) of the above bolt patterns:
  • So it is always advisable to measure what you have to be sure and get a spacer that will fit your vehicle.
  • Also, front and rear drive shaft bolt patterns may be different, so measure the one you intend to install the spacer on.
  • Each end of each drive shaft may have a different bolt hole pattern, so be sure to measure the end of the drive shaft that you intend to put the spacer on.
  • Realize that the information in the above table does not mean that the listed bolt pattern is THE ONLY bolt pattern used on a given vehicle.
    • Rather, it lists where that given bolt pattern was introduced and is typically used, but there may be other bolt pattern(s) present on a given vehicle.
    • So for example, on the newer Tacoma and 4Runner models, they MIGHT have one or more 65mm x 65mm pattern flanges, but they also might have one of the earlier u-joint or CV joint patterns as well and in fact they might not have any flanges in the 65mm x 65mm pattern.
  • You might be tempted to use information posted on-line about what someone else used on their truck. But in the end, what matters is what bolt hole pattern you have on your truck and not what bolt pattern someone else has.
  • In case you did not get the message, we HIGHLY recommend that you measure the bolt hole spacing on the flange you intend to install the spacer prior to ordering.
    • It is typical to have 2, 3 or even 4 different bolt patterned flanges on a single vehicle.
    • But if you do end up with the incorrect pattern spacer (it happens), we'll be happy to swap it out for the proper one, as long as the old spacer is unused.
• Bolt hole spacing is measured from adjacent bolt hole center to bolt hole center.
  • On square patterns, both sides will of course measure the same.
  • On the rectangular patterns, there will be a long and short side.
  • Note, these are not diagonal or bolt hole circle dimensions (like you find on wheels):
    • Basically think of the length and width of the square/rectangle formed by the bolt hole centers.
    • And if it is easier, you can measure from leading edge to leading edge of the holes instead of the centers.
      • Just don't make the mistake of measuring from the leading edge of one hole to the trailing edge of the other, since that will give inaccurate readings.
      • For example on the 60mm x 60mm pattern, if you measured from the leading edge of one hole to the trailing edge of the adjacent hole, you would have 60mm + 10mm (the size of the bolt hole) or 70mm total.
• The standard triple-drilled spacers directly fit the bolt patterns listed in RED in the table above.
• (*) For the '79-'83 pickup rear drive shafts (that use a 60mm x 60mm x 8mm bolt pattern) there are several options available:
  • The first option is to re-drill the transfer case and drive shaft flange holes to 10mm to accommodate the larger, late-model 10mm bolts.
    • Simply order the regular spacer in the thickness desired.
• (**) For the '79-'83 pickup rear drive shafts (that use a 56mm x 64mm x 8mm or 9mm bolt pattern) there are several options available:
  • The first option is to order an un-drilled spacer and then drill the spacer to match the flange on the drive shaft.
    • If this option is chosen, you'll be getting the 10mm hardware, so plan on drilling out the flanges to fit the 10mm bolts.
  • For the 8mm bolts, another option is to order sleeves to step down the spacer hole size from 10mm to 8mm. They cost $15.00 for a set of 4.
    • In addition, 8mm bolts and nuts are available for a cost of $15.00 for the set of 4 alone, or $10.00 additional in place of the standard 10mm hardware.
    • So, for a spacer with 10mm holes, a set of 4 - 10mm/8mm sleeves and 8mm hardware (in place of the 10mm hardware), add $25.00 to the cost of the desired spacer. Allow approx. 1 week extra time for the sleeves and hardware as they are special order items.
  • '79-'83 front shafts typically use a CV joint, usually with one of the triple-drilled bolt hole patterns, but possibly with an 8mm bolt, vs. the 10mm bolt. So the above options apply to front shaft spacers; that is drill a blank spacer, drill out your flanges for 10mm bolts or order smaller bolts and 8mm/10mm sleeves.
  • Note: The 10mm flange bolts typically have a 14mm head (i.e. size of wrench needed to fit the bolt), while the smaller bolts will have a smaller bolt head, on the order of 12mm..
• (***) Some Tacoma pickups use a 65mm square bolt pattern on the CV joint.
  • Please be sure to measure the bolt hole spacing of the flange you intend to put the spacer on as the front and rear flanges may be different.
  • Also note that on rear 2-piece drive shafts, the flange off the carrier bearing will likely be a different pattern than the transfer case flange, usually something like 60mm x 60mm, so be sure to check the bolt pattern on the flange you wish to install the spacer before ordering!
  • This same bolt pattern may also be used on some 3rd generation 4Runner on the pinion flange and again the pattern on the pinion/axle end of the drive shaft is likely a different pattern than on the transfer case end. So be sure to know which pattern you have on the end of the shaft that you intend to put the spacer on prior to ordering.
  • Some Tundra and Tacoma pickups also use this same bolt pattern including the 2WD pickups
    • On the 2WD pickups (Tundra and Tacoma), this bolt pattern is present on the pinion flange, which is where the spacer is installed since the upper end of the shaft slips into the tail housing of the transmission.
• (****) For the FJ Landcruisers, the 56mm x 64mm x 10mm bolt pattern is likely but one of many bolt patterns.
  • This is but one pattern we are aware of.
  • The FJ-40s may also use the 61.5mm x 70mm x 10mm bolt pattern that is included in the triple-drilled spacers.
  • So again, please measure what bolt pattern your truck uses prior to ordering. Because Toyota does not go by our table on what drive shaft pattern goes on what vehicle. We only know what patterns are used based upon what our customers have told us that they have found on their vehicles. So the bolt pattern that your truck has is what it has.
• The FJ-80 and LX-450 models with the high pinion 8" front differential often use the basic 60mm x 60mm bolt pattern.
  • Of course the same applies to solid front axle applications that use the FJ-80 high pinion front differential.
• Also available are un-drilled spacers.
  • If the above bolt hole patterns do not fit your requirements, you can purchase an un-drilled spacer then drill it to fit your drive shaft flange. This would be applicable for the 1st gen 4WD pickups which use the smaller 8mm drive shaft bolts or for some of the later model Toyotas that use a pattern different than above.
    • For the 8mm bolt applications, a hardware kit is available for $10.00 additional.
  • These spacers will also work with the FJ-40 and FJ-60 Land Cruisers, after marking and drilling the blank spacer to match the drive shaft flange bolt pattern.
    • These vehicles typically use an 11mm flange bolt (~7/16").
  • Another application for the un-drilled spacers is if you want to fabricate an adapter to mate one sort of drive shaft flange to another sort of t-case or pinion flange.
    • For this application, you would drill one side of the spacer for each pattern, rotating the flange ~45° in between to offset the two sets of holes.
    • Then, tap the holes for a threaded stud or countersink the holes for a pressed-in through-bolt or stud and then insert studs, 4 facing one side and 4 facing the other side.
    • Then you can bolt the spacer/adapter to the t-case or pinion flange with one set of studs/nuts and then attach the drive shaft flange with the other set of studs/nuts.
• And what if you need more than 1.5" of additional drive shaft length? Of course, the "best" option is to have the shaft lengthened, but that is also fairly expensive.
  • While you really do not want to "stack" spacers, there is no rule that says you can't put one on each end of the drive shaft.
  • After all, the shaft has 2 ends and unless you have a 2WD with the upper slip yoke connection, you'll have a flange at both ends of the shaft.
  • With the available bolt patterns, you should be able to find a spacer to fit on each end.
    • On most 2WD models, you have to put the spacer at the pinion flange at the rear differential, since the transmission end of the drive shaft is typically a slip yoke.
• If you have other questions about the spacers, click here...

What makes the 4Crawler Offroad spacers different?

So, what makes these spacers different? Well, we were one of the first companies offering a Toyota-specific drive shaft spacer. In designing our spacers, we studied the market and picked the most popular set of drive shaft flange bolt patterns to support. As such, we offer the widest variety of patterns and spacer sizes available on the market. We also offer blank, un-drilled spacers for those cases where you may have a unique pattern or application. And over the years, we have increased our product offering by adding the newer 65mm x 65mm pattern as well as the older 56mm x 64mm pattern to support those applications as well.

Also, we only use real metric bolts, unlike some of the other spacers out there, which use undersized SAE hardware. Also, we use grade 12.9 hardware, meeting or exceeding the specs. of the factory grade 11 hardware. And also, we list the exact bolt patterns of each of the spacers, so you can check which one meets your needs before you order. Since there is such a wide range of bolt patterns that have been used over the years on a wide variety of vehicles, it is hard to list a spacer that fits any given year/model vehicle. Also, with the popularity and ease of swapping parts from one vehicle to another, you may have a 'XX 4Runner with a transfer case from a 'YY pickup and a drive shaft from a 'ZZ Tacoma, and deciding what "year" your vehicle is for purposes of selecting a spacer for is pointless.

On-Line Ordering:

Order a drive shaft spacer below:

• Triple drilled spacers
• 65mm x 65mm spacers
• 56mm x 64mm spacers
• Blank/Un-drilled spacers

In-stock spacers (as listed below), typically ship within 24 hours via Priority Mail, typical delivery time:

• 2-3 days US
  • Upgrade to Express 1-2 day US shipping with the shipping upgrade button below:
• 6-10 days international
  • International shipment are not insured and only minimally trackable.
  • Upgrade to Express/EMS 3-5 day insured and fully trackable international shipping with the shipping upgrade button below if you are the type of person who is concerned by inability to track a shipment or who is concerned about loss or damage in transit.

Want the spacers shipped faster?

Express Delivery upgrade; US$20.00 (for both US and international shipments).

Triple-drilled spacers:

• Inventory:
  • Size--------------Part Number-----Status
  • 0.75"/19mm - DSpcr3X_0.75 - In-stock
  • 1.00"/25mm - DSpcr3X_1.00 - In-stock
  • 1.25"/32mm - DSpcr3X_1.25 - In-stock
  • 1.50"/38mm - DSpcr3X_1.50 - In-stock

0.75" Spacer; US$65.00	1.00" Spacer; US$68.00	1.25" Spacer; US$71.00	1.50" Spacer; US$74.00
US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00
International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured

65mmx65mm drilled spacers:

• Inventory:
  • 0.75"/19mm - In-stock
  • 1.00"/25mm - In-stock
  • 1.25"/32mm - In-stock
  • 1.50"/38mm - In-stock

0.75" Spacer/65mm; US$65.00	1.00" Spacer/65mm; US$68.00	1.25" Spacer/65mm; US$71.00	1.50" Spacer/65mm; US$74.00
US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00
International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured

56mmx64mm drilled spacers:

• Inventory:
  • 0.75"/19mm - In-stock
  • 1.00"/25mm - In-stock
  • 1.25"/32mm - In-stock
  • 1.50"/38mm - In-stock

0.75" Spacer/56mm x 64mm; US$65.00	1.00" Spacer/56mm x 64mm; US$68.00	1.25" Spacer/56mm x 64mm; US$71.00	1.50" Spacer/56mm x 64mm; US$74.00
US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00
International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured

Un-drilled spacers:

These spacers are the perfect solution for a custom application, you can drill them to match your driveshaft flange. Also as another option, you can use these spacers to make a bolt pattern conversion by drilling and tapping bolt holes in one side for one pattern and then offsetting and drilling/tapping a 2nd set of holes for a 2nd bolt pattern on the opposite side. You could also install threaded studs in place of bolts if that suits your application.

• Inventory:
  • 0.75"/19mm - In-stock
  • 1.00"/25mm - In-stock
  • 1.25"/32mm - In-stock
  • 1.50"/38mm - In-stock

Un-driilled spacers will come with 10mm metric hardware unless otherwise specified.

0.75" Spacer/un-drilled; US$65.00	1.00" Spacer/un-drilled; US$68.00	1.25" Spacer/un-drilled; US$71.00	1.50" Spacer/un-drilled; US$74.00
US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00	US Delivery; $8.00
International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured	International Delivery; US$24.00 - not insured

Notes:

• Your order will be shipped via Priority Mail for domestic (US addresses, including APO/FPO) with a delivery tracking number provided at time of shipment.
  • 2-3 days delivery time typical, expedited shipping available at an additional cost.
• International orders will be shipped via US Priority Mail International by default
  • 6-10 days delivery time typical, expedited shipping available at an additional cost.
• Unused parts may be returned for a refund, less the cost of postage on the original shipment and a 10% restocking fee.
• Please be sure to double check your shipping address, both that it is correct and that it is able to receive US Mail deliveries.
• Also, international shipments require a local telephone number for customs paperwork, include that in the "Note To Seller" field of the order form.
  • Lack of phone number will delay shipment of the parts.

Returns/Exchanges Policy:

• Exchanges:
  • If an exchange is desired, please include a note as to what exchange part you want and include return postage for that part to be sent back to you.
    • Return postage will be be as noted above, typically what the original item shipping was.
  • If you are in a rush to get the exchanged part, place an order for the new part and we'll ship that to you right away. Then return the old part, and upon receipt, we'll issue a refund against the new order.
• Parts may be returned for a refund within 60 days of original purchase.
  • No need to obtain an RMA number or anything like that.
  • A 10% restocking fee will be deducted from original purchase price less outgoing shipping.
    • Parts must be in new and unused condition for the refund.
      • Used or blemished parts can yield partial refunds at the discretion of 4Crawler Offroad.
      • Parts that have been modified by the customer or that have been built to unique customer specifications are generally not refundable.
      • Returned items with missing components will have the refund adjusted for the cost of the missing items (e.g. missing nuts or bolts, etc.)
    • The customer is responsible for return shipping charges.
    • Returned parts must include a copy of the original invoice or packing slip for proper credit.
    • It is highly recommended that a package tracking number be obtained from the shipper and that that number be transmitted to 4Crawler Offroad so that we are aware that you have sent an item back and that we can track it, know when it arrives and can pick it up at our PO box.
      • If you use the USPS.COM on-line shipping label system, you can get the delivery/tracking number at no additional cost and you can simply enter our e-mail address (sales@4crawler.com) in the recipient field and we'll automatically be sent that information.
      • If you don't have a tracking number, at least send us an e-mail noting when and how you shipped the package so we can keep an eye out for it to arrive.
  • One exception to this policy is in the case that the parts do not fit properly, per the installation instructions.
    • The returned part(s) must be accompanied by photos or a detailed description of the fitment issue.
    • In such a case 4Crawler Offroad will refund the full purchase price less shipping. And as noted, please furnish a detailed description of the fitment issue reported, including dimensions, so that this fitment issue may be corrected for future orders.
  • Items returned 60 days or more past the purchase date will be refunded less any applicable transaction fees, typically 4% - 5%.
    • This time is from the date of purchase until we get our hands on the returned item(s) so we can inspect them for missing parts or damage, so be sure to allow enough time if planning to return an item for a refund.
  • Items that are custom built to fit customer specifications may only be returned for partial credit at the discretion of 4Crawler Offroad.
• Return to:
  • 4Crawler Offroad Products
  • attn: Roger Brown
  • PO Box 61092
  • Sunnyvale, CA. 94088-1092
  • USA
• Physical shipping address can be provided for UPS/Fedex return shipments if requested.

Installation Instructions:

Installed spacer on transfer case output flange

Allow approximately 30 minutes for the installation, assuming you don't run into any rusted or damaged fasteners. To remove the stock hardware, you'll need a pair of 14mm wrenchjes and to install the spacer 10mm hardware, you'll need an 8mm long arm allen key and a 17mm wrench.

While you should not have to separate the drive shaft to install the spacer, it is a good idea to put an alignment mark across both sides of the slip yoke. Some white paint works well and will help you re-align the slip yoke if you accidentally pull it apart.

Typically, the stock drive shaft (a.k.a. propeller shaft) flange bolts use a 14mm head, so you'll need a pair of 14mm combination wrenches to remove those. For the rear drive shaft, block the vehicle's tires or place the rear axle on jack stands for easier removal. You can place the transmission in neutral and release the parking brake if needed.

The spacers can be installed on either the upper or lower end of the drive shaft, depending on application and bolt hole patterns. On 4WD trucks, they are typically installed at the transfer case companion flange. 2WD trucks will only be able to install them at the pinion flange on the axle, but no reason 4WD trucks can't do the same. And it would not be out of the question to install two spacers on one drive shaft if you need to extend it more than 1.5", putting one spacer on each end of the shaft.

Break the stock flange bolts loose at the transfer case and then remove them. Support the drive shaft before removing the last bolt to keep it from falling. Then compress the slip yoke enough to allow insertion of the spacer.

Note:

Some transfer case flanges have pressed in studs instead of separate bolts. In this case, you'll need to hammer or press the studs out. You can spin a nut on the end of the stud before hammering it out to protect the threads. The supplied longer bolts will replace the studs.

Then slip the spacer in between the transfer case output flange and the drive shaft flange and turn it to make sure you have the proper set of 4 bolt holes in alignment. Slip in one of the supplied metric socket head cab screws, a lock nut and washer (if needed). Repeat for the other 3 bolt holes, just to make sure all 4 bolts are installed before tightening them. If you find the bolts hard to install, use a small round file to clean out the insides of the holes in the flanges to make installation easier.

For un-drilled spacers, you'll want to use the existing flange to mark the spacer for the location of the new bolt holes. The spacer can be clamped to either the drive shaft or transfer case flange, probably easiest to remove the flange from the transfer case output (30mm staked nut holds it in place) and use that, clamping it to the spacer so it does not move. Select a drill bit that just fits inside the bolt hole or use a transfer punch to mark the hole locations. If you are unsure of your drilling skills, you may elect to mark and drill one hole at a time and then use that freshly drilled hole and a bolt to secure the spacer to the flange for marking and drilling the next hole. Once the hole location is marked, remove the flange and drill out that hole (a drill press works best to ensure a straight hole). Use a bit that is as big as or slightly larger than the hole in the flange. Once all 4 holes are drilled, make sure all 4 bolts fit into the flange, spacer and drive shaft before proceeding. If you find a slight misalignment, you can run your drill bit through the holes to open them up a little bit if needed. For the standard 10mm bolts, you generally want to drill the holes with a 10.5mm bit or a 13/32" or 27/64" drill bit.

Once all 4 bolts are in place, alternately snug them down with an 8mm allen key (a long handled key is recommended) and a 17mm wrench (for the nut). Once all 4 nuts are snugged down, torque the nuts to approx. 45 ft.lbs. and re-check the torque after 50-100 miles of driving.

Questions? --> <-- Comments?