Rear Axle on Work Truck

[backporch]

If the problem turned out to be worn pinion bearings, is that a reasonable DIY fix? Any special tools required.

I haven't looked into the repair yet, but the general consensus that I hear is that the differential requires some experience to get it right.

 

[Dirtman]

You need a dial inch pound torque wrench, a dial indicator, a new crush sleeve, and a shim kit. It's not difficult but not simple either. You don't just slap new bearings in, you have to reset the preload, backlash, and carrier/pinion mesh which requires patience and finesse.

 

[Curious Hound]

Not an easy fix. Requires bearing pullers and s hydraulic press for re-installation. Torque wrench capable of almost 200ft-lbs for torquing the pinion nut plus the stuff mentioned above.

 

[rusty ol ranger]

My experience doesn't support your statement. I had a b2 that I swapped in axles with what I was told was 4.10 gears in front and back. Came to find out that it was 4.10 in front and 3.73 in back. It was apparent quite quickly that something was wrong so I didn't use 4x4 much after finding out. But on soft dirt and grass there is lots of slip to compensate.
I say this just as information....I do NOT recommend putting in different gear ratios.

Alot of mud truck guys will run a higher gear in the front axle then the rear, just so the front floats better due to higher overall wheelspeed givin any certain RPM.

Either way yes its a bad idea on anything but a dedicated mud truck.

 

[Dirtman]

Old dodge trucks always had a slightly lower front gear from the factory. Only like 4.11 vs 4.10 but it was designed to do make the front end pull instead of being pushed so it would handle better in slippery conditions.

 

[4x4junkie]

My experience doesn't support your statement. I had a b2 that I swapped in axles with what I was told was 4.10 gears in front and back. Came to find out that it was 4.10 in front and 3.73 in back. It was apparent quite quickly that something was wrong so I didn't use 4x4 much after finding out. But on soft dirt and grass there is lots of slip to compensate.
I say this just as information....I do NOT recommend putting in different gear ratios.

Even on dirt there's still enough stress created that after some time, something could break just from fatigue. However I do agree most likely it wouldn't be on the very first time you did it. (wet grass, and of course mud, generally won't allow as much stress to build up).


To the OP:
I would suggest to just keep checking around your local wrecking yards for a 4.10:1 axle (also check Craigslist for people parting out vehicles too). 4.10 isn't exceptionally rare on 4x4 Rangers built after 1998 (4-cyl Rangers earlier than this often have them too, though these will be 7.5" axles).

 

[RonD]

The statement of "it WILL blow up" was to make a point
And a good one

Yes, there are all sorts of things you can insert for a "work around" for the statement, lol

You could run 29" tires on the front with 4.10 axle, and 26.4" tires on the rear with 3.73 axle, although the, "just don't do it" would be what I would recommend


And you don't need to run a different ratio up front to pull better in the mud or ??, just have a set of 1"-2" smaller tires to put on the front when needed

 

[backporch]

All makes sense. Thanks. I think I am going to hang tight for now and keep the usage down. Maybe in warmer weather consider a swap or teardown. Hopefully I don't encounter a failure before then, but I probably won't stray far from home.

 

[backporch]

just contacted a manufacturer of bearings/gears and he said that the whine on power and quiet on coast sounds like a gear wear issue, not a bearing problem.

I also noticed their bearing kit does not come with shims and he said that usually you can install the original shims with some success, but would have to verify the contact pattern.

 

[backporch]

Since it looks like a used axle is probably my best bet, are there other vehicles that I can pull an axle from? Mustang? for a 99 ranger with 4:01 in an 8.8 rear?

 

[sgtsandman]

It’s best to get a Ranger or Bronco II axle with the gearing you need for the quickest and easiest swap. Anything else is more than likely going to need some fabrication work to make it fit.

 

[sheep herder]

Even if a Mustang axle is the correct width, mounting is completely different.

 

[don4331]

Since it looks like a used axle is probably my best bet, are there other vehicles that I can pull an axle from? Mustang? for a 99 ranger with 4:01 in an 8.8 rear?

You want '93-09 Ranger axle. The ideal axle is an '03-07 FX4 LII - big bearings like Explorer and probably ratio you want.

'83-'92 Ranger axles are narrower, BII axles have spring pads in wrong place (too narrow - you can make work, but it isn't "right"), '10-11 Axles don't have the speedometer sensor in the housing. Mustang axles are MUCH wider - goes with the greater backspace rims, and use coil, not leaf springs (unless you are getting really old).

 

[09fx4guy]

Agree with above- try to find an axle out of an 03-07 FX4 Level 2, or 08-09 FX4 with a Torsen limited slip and 4.10 gears. In a pinch, any Ford Ranger 8.8 from the 93-09 with a 4.10 ratio would work. Then it would be a direct swap without any spring perch mods, etc.

You should be able to find one in a junkyard for a decent price. Look on car-part.com

 

[backporch]

Thanks... Now I have a good idea what to look for. My diff is open, I guess limited slip works and is more desirable?

I had been looking locally through craigslist and was trying to find a "lower" mileage truck that somebody was parting and specifically asked if the rear end was quiet. I didn't want to buy something from a seller who bought a parts truck and had never driven it.

Any suggestions what to look for? mileage, physical characteristics of an axle to have a good chance of swapping to something better? Junk yards are typically good at taking back parts that have issues, but I am also trying to avoid swapping the axle more than once.