Here's a good one for you guys....

[DougInNJ]

I bought a 95 Ford Range 4x4 knowing the 4wd didn't work. I am a back yard mechanic and I couldnt figure it out so I took it to be repaired. My mechanic put a new motor in the transfer case and replaced the stock locking hubs with a pair of Warn manual hubs.
The 4wd drive now works fine, but.....with the hubs locked and when I engage 4wd Hi I noticed the rear tires were digging in and "pushing" the front tires. Same thing happened in 4wd Lo. My mechanic thinks the front and rear differentials are different and the rear axle may have been changed. He took a look and there is no tag on the rear differential housing.
Now what? How can i tell if the front and rear differentials are the same or different?
or could my mechanic have done something wrong when he was inside the transfer case?
Any experience or suggestions would be appreciated.
Thanks Guys
Doug

 

[alwaysFlOoReD]

I agree with your mechanic.
It's been a long time since I did the following, so do some searching. Put truck on axle stands, all wheels in the air. You can get a close estimate of gearing by turning the wheel [tire] [keeping count of revolutions] until the driveshaft rotates once. 3.5 turns = 3.5 to 1 ratio. Make sure both tires on an axle are turning at the same speed, if not hold one still and IIRC divide the result by two. I'm not sure about the front axle, I think removing the driveshaft from the diff would be necesary...I've never done the front. You could also fire up the truck, place a chalk mark on the tires, and carefully engage the trans. You will be able to see if one set of wheels is spinning faster than the other. Use the brake to slow the tires down with an auto. Clutch in and then brake with a manual.
Please be careful,
Richard

 

[Captain Ledd]

Yeah, sounds like 2 different ratios. The rear axle is geared faster than the front.

You can check the door code to see what the proper ratio/axle should be.

http://www.therangerstation.com/tech_library/axle_codes.shtml

But chalking the tires or otherwise counting revolutions are about the only non invasive things you can do. If you really want to know definitively, pop the cover on the rear axle, the ring gear should have 2 numbers on it, along with some other part numbery/reference looking things. They should be distinct and divide well into 3.55/3.73/4.10/etc.. Divide the larger one by the smaller one. EX: 41 10 = 41÷10 = 4.10 rear ratio.

 

[DougInNJ]

Thank You

Thank You Guys. I knew I could count on the experience in this forum. Great ideas and i will suggest or try them all.
Doug

 

[Captain Ledd]

I should add, the front axle ring gear will also have those numbers on it, but is much more of a pain to get to. They're tooth count numbers for the R&P.

 

[4x4junkie]

Jack one side up and spin the wheel exactly TWO revolutions while counting how many times the driveshaft turns is generally the best way to find the axle gear ratio (front or rear axle it's the same process, just make sure both hubs are locked if checking the front).
Like alwaysfloored said, 3.5 turns of the driveshaft = 3.55:1, 3¾ turns = 3.73:1, and so on.

This will work for both an open or limited-slip differential. If the axle happens to have an aftermarket mechanical locking diff in it though, then you'll need to jack up both sides and then rotate the wheel(s) once rather than twice.

 

[alwaysFlOoReD]

^^^ thanks for the clarification. It's been awhile since I've done that and wasn't very clear.