Yukon Gear & Axle User manual

Yukon Gear & Axle
Ultimate 88 Axle Kit Installation Manual
© COPYRIGHT 2011 - Yukon Gear & Axle
PLEASE READ COMPLETELY BEFORE INSTALLATION

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Parts List
• Items 10 & 11 are used for setup only, see steps 23 & 24 for clarication.

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Thank you for purchasing the Yukon Ultimate 88 axle kit. This kit will eliminate the need for C-Clips and improve the
functionality of your Ford 8.8 rear axle. Reading these instructions before you start will facilitate the installation
process. When working under the vehicle be sure to use jack stands under the axles. Wear safety glasses and
gloves. Before disassembly ensure that you have a Ford 8.8 31 spline disc brake rear axle from a Ford Explorer and
that you have all of the required tools listed below. Please note that this kit will widen your axle by approximately
0.96” on each side.
Required Tools
Safety Glasses
Jack and Jack stands
Wheel Chocks
Grinder
Cut off Wheel
Torque Wrench
Shop Rags
Deburring Tool
Appropriate Wrenches, Screwdrivers, Socket Set
Axle Grease
Gear Oil
Oil Catch Pan
Hydraulic Press
Installation
1. If working from the ground place one wheel chock in front of the drivers side tire and the other wheel chock
behind the tire.
2. Lift and support rear axle with jack stands under the axle housing.
3. If using a lift, position lift arms in secure positions under frame of vehicle and lift vehicle.
4. Remove the rear wheels.
5. Drain gear oil from differential.
6. Remove differential cover.
7. Remove cross pin bolt using 5/16” wrench.

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8. Remove cross pin.
9. Remove calipers.
10. Remove rotors.
11. Push in axles and remove c-clips.
12. Remove the axles and place a rag into the ends of the axle tubes to prevent debris from entering.
C - CLIP
CROSS PIN
CROSS PIN BOLT

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13. Remove caliper bracket and dust shield assemblies.
14. Remove outer housing seals and wheel bearings.
15. Clean and inspect the housing ends. Note that there is a small shoulder area as well as a tube
that houses the bearing and seal. The tube area will need to be cut down ush with the shoulder.
16. Cut the ends of the housing FLUSH TO THE SHOULDER.
CUT
SHOULDER
FLaNgE

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17. If necessary use a grinder to nish the cut ush with the shoulder.
18. De-Burr the inside and outside of the cut.
19. Remove the shop rags from the housing and clean out any debris.
20. Silicone the recess on the back side of the bearing seats.
21. Press the bearing seats onto the housing WITH THE FLAT SIDE UP.
22. Use the supplied 3/8” bolts and slide them in through the back.
23. Slide the (4) large 7/16” spacer nuts over the bolts and thread on the (4) 3/8”-24 non-locking nuts.

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24. Tighten the nuts in a cross pattern to seat the bearing seats to the housing.
25. Remove all 8 set up nuts and set them aside.
26. Slide the caliper bracket and dust shield assemblies over the 4 bolts.
27. The axles are double drilled for 5X4.5” & 5X5.5” bolt patterns. Use the pattern that matches
your application.
28. Before installing the wheel studs, thoroughly clean the threads in the axle ange and on studs to remove oil
and grease. Apply a drop of high strength thread locking compound to the threads near the head
of the studs.
29. Thread the (5) ½” studs into the ange of each axle and tighten to 90 ft. lbs.

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30. Slide the retainer plate, spacer, bearing seal, bearing, and bearing retainer onto the axle in the
order shown below.
31. Using a hydraulic press, press the bearings onto the axles.
32. Apply a thin coat of silicone to the seal areas.
33. Slide the axle shaft assemblies into the rear axle. The long shaft is for the driver’s side, short shaft is for
passenger’s side.

34. Using the access hole on the axle ange, thread the 3/8” grade c lock nuts onto the 4 bolts over the
retainer plates.
34. Torque nuts to 40 ft. lbs.
35. Slide on the brake rotors.
36. Fasten the calipers.
37. Mount wheels and tires and torque to factory specication.
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38. Re- install diff cover.
39. Fill differential with gear oil.
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For Your Records
Name _______________________________________________________________________________________
Date ________________________________________________________________________________________
Invoice Number _______________________________________________________________________________
Yukon Part Number ____________________________________________________________________________

Yukon Gear & Axle (“Yukon”) warrants the original retail purchaser that all Ultimate 88 Axle Kits will be free from defects in materials
and workmanship for the period of one (1) year from date of sale. Yukon makes no other warranty of any kind, express or implied. All
other warranties, including but not limited to an implied warranty of merchantability or tness for a particular purpose, are excluded.
This warranty is offered provided that the Yukon product has been installed and maintained in accordance with Yukon instructions,
and that it has not been subject to modication, accident, abnormal use (including off-road or competition use) or misuse. This
warranty is void if installation of Yukon product(s) occurs on vehicles with tires that exceed Yukon Maximum Recommeded Tire Size.
Upon notication of a warranty claim, Yukon shall investigate the claim of defect, and, in the event of a veried defect, shall, at their
sole choice, either repair the defective product, replace it, or refund the purchase price.
This warranty does not cover, and Yukon shall not be liable for, incidental or consequential damages, including loss of time, road
service charges, labor charges, inconvenience, loss of vehicle use, loss of revenues, or loss or damage to personal property
(including loss or damage to vehicle parts due to the failure of the Yukon product). In addition, this warranty does not cover, and Yukon
shall not be liable for, any undertaking, representation, or agreements made by dealers or other third parties selling Yukon Gear &
Axle products, except where such agreements are within the provisions of this Warranty statement. Also, this warranty does not
cover damage to the axle caused by or facilitated by failure of a non-Yukon component.
This agreement offers you specic legal rights. You may also have other rights which vary from state to state.