47-55.1 Explorer 8.8 swap

[Stewy49]

Was wondering if anyone that has done the Explorer offset 8.8 swap had any driveline issues at highway speeds or any other problems after doing the swap. Thanks!

[mr48chev]

Why would you have driveline issues if you had a proper driveshaft made for it?

[whitedog76]

There really isn’t an issue with offset axles. Manufacturers have been doing it for years to compensate for fuel tanks, exhaust routing etc... As long as you’re engine/trans are 90 degrees to your rearend.

If you have a speed square hold it on it’s perpendicular axis. The angles stay the same regardless if it’s horizontal or verticle.

It’s pretty common to pitch the rearend down 1/2 to 2 degrees to compensate for axle wrap, with an offset axle you would lean more to the 1/2 degree side of things.

[Stewy49]

Thanks for the reply's, I wasn't sure if there would be any problems if the motor/trans wasn't in a straight line with the center diff.

[Shinysideup]

I dunno, mine works fine with the exploder rear.

[jweb]

I have no problem with mine but there are a few things to think about if you already have wheels. The Explorer axle is narrower than the stock axle and 5x4.5 bolt pattern

I just bought some high quality 1" wheel adapters. They are hub centric on the axle and inside the wheel. I have 20x9.5 wheels and this makes them perfectly centered.

[FAKKY]

Originally Posted by whitedog76

As long as you’re engine/trans are 90 degrees to your rearend..

? not quite following here

[whitedog76]

Originally Posted by FAKKY

? not quite following here

Your engine and trans are parallel to the frame, the rearend is perpendicular.

[jweb]

Here's some good info on driveline angle:
https://www.hotrodhotline.com/md/htm..._harmonics.php

[28TudorAZ]

I put an explorer rear end in my Ford Tudor. I am having issues with it making some vibration at higher speeds. I do not think it has anything to do with the offset to one side. I think it might be a axle bearing but haven't had the time to pull it. I would just keep in mind most of them that you pull from a junk yard have high miles and you may want to replace the bearing and seals since you are in there. I wish I would have.

[Stewy49]

Thanks everyone. I did plan on going through it and replacing bearings and seals.

[65blackfleetside]

I installed an offset 8.8 explorer axle. Limited slip 373 with disk brakes. Had a machine I shop drill the axles and new rotors to chevy spects. Fits perfectly no spacers required. just over $300 total investment.
I also had the drive shaft balance and universal joints replaced by driveline shop. ($120)- hopefully this will eliminate any vibration once I get the truck on the road. Unbalanced drive shafts will cause lots of headaches.

[dsraven]

u joints are automatically prone to make a vibration but they will cancel each others vibration if they run at opposite angles to each other. that means if the engine has a downward slope of, say, 3 degrees then the differential pinion should have an upward slope of 3 degrees (at ride height of the truck) so the two ujoints will cancel each other out. this get complicated when you run a suspension that is prone to "spring wrap-up" under acceleration or if the angles get bigger than a ujoint should be run at. when the springs wrap up under acceleration the angle of the pinion changes to be different than the engine, which basically doesn't change, so a vibration is noticed.
now if you take that theory and add the offset pumkin you can see that it becomes important to ensure the engine/trans is parallel to the frame and the rear axle is at 90 degrees to the frame. this will help keep the offset angles of these two parts the same so they will cancel each others vibration.
to check if the engine/trans is running parallel, make a mark on the center of each cross member from the front to the rear (that is assuming the engine is in the middle of the frame rails). now run a string line or a laser down the marks, front to rear, and see if the trans output shaft and the engine front pulley are in line with the center line you just established. doing this will also show if the frame is straight. if one or more cross members is not in the middle then the frame is not straight. if you find there is "stuff" in the way of a string line or laser (like bodywork, fuel tanks etc), the marks can be transferred to the (clean) floor (masking tape and a sharpie work well) using a plumb bob and some time. drop a line and mark the floor off each corner of the frame, at each cross member center mark and at the engine crankshaft center line and the trans output center line. you can connect the dots with a chalk line and then do measurements. a corner to corner check of the frame is also a good idea at this point. usually a 1/8" out of square is acceptable. next would be to check the axle to ensure it is at 90 degrees to the frame or at least 90 degrees to the engine/trans center line. you cab do this by dropping a line from each axle flange center line, then measuring from each of these marks over to the mark on the floor from the trans output or some other mark in the center line of the frame. obviously a mark further away from the axle will give a more accurate measurement.
below is a link with a pic of what axle wrap looks like. it is when the spring tries to bend into an S shape in front of the rear axle. you can see how this would negatively affect the pinion angles. some guys will offset this by using a pinion angle that is a bit off angle so when the vehicle is under power the angle change is lessened. some will use a traction bar or a ladder bar to keep the axle housing from rotating under power
https://www.dragzine.com/tech-storie...g-suspensions/
hope this helps

[dsraven]

sorry, forgot to say the check for the rear axle being 90 degrees to the frame would assume the axle is also centered in the frame, side to side. otherwise those measurements from the axle flanges to a common center point would be skewed.
if you did the plumb bob thing with marks on the floor, drop a line down from each rear axle flange center. chalk a line on the floor to connect the frame center line marks from front to rear and measure out from that chalk line mark to each axle flange mark to ensure they are both the same dimension to prove the axle housing is in the middle. then do the diagonal to a common center point after that is established.
thats just my way, lots of other methods probably coming right up