warm differential

[nisse]

I just replaced the pinion seal on the rear differential on my 2003 Ranger, I took it for about a 15 mile test drive and it drove fine and it looks like the leak is gone. I did however notice the differential was fairly warm when I got back, I could keep my hand on it but much warmer and I wouldn't be able to. Is this normal?
Thanks,
John
P.S. The exhaust is a fair distance away nothing around the differential was warm
 

[buickanddeere]

Minimal loss of 1-2% of power through each gear to gear contact.
So 50HP or the equivalent of a 3.75KW heat applied to the diff for 15 minutes.
Yup, it will warm up.
 

[nisse]

Thanks for the reply, I figured it was fine just wanted to make sure, first time I have done this job.
Thanks,
John
 

[Cas]

I always wondered about heat produced in gear to gear contact. Thanks for the answer.
 

[MarkB_MI]

After you replaced the pinion seal, how did you adjust the pinion preload? If you don't know what preload is, then I can tell you what your problem probably is. Remove the driveshaft and try to turn the yoke by hand, if it won't turn easily, the preload is probably too high. If it's a little bit tight, the pinion bearings will loosen up in time. If it's way too tight, the bearings will fail.

Unfortunately, if you've overtightened the pinion nut, it's not a simple matter of loosening the nut to reduce preload. There's a crush tube between the yoke and pinion gear, and once you overshoot the correct preload the only way to reduce it is to replace the crush tube and start all over again.
 

[the tractor vet]

Ah yes ford and there stupid crush spacers . And replacing the old with new on old bearing and trying to get a GOOD rolling preload . After eating a ring and pinion on my 88 F350 due to it self crushing while backing a load up a hill i did away with it and had the machine shop i delt with make me up some solid spacer in different thickness. Yea it took a bit to get the rolling preload on the bearing but once set it was set never to move again . Shortly after mine went out i did five more back to back for customers . Two had two failures before and non after my barnyard repair.
 

[nisse]

Thanks for the information, I will see how the yoke turns. When I took it apart I made a couple reference marks on nut and counted turns on the nut, also made a measurement with caliper to make sure I wasn't a turn off. Ended up about a quarter turn short when I tightened nut back up.
John
 

[MarkB_MI]

Hmm. If it's indeed a quarter turn short, that would mean insufficient preload. You wouldn't even be in contact with the crush sleeve, and the nut usually needs it a bit tighter than before to compensate for bearing wear. I'd expect the rear end to be noisy if you didn't get enough preload, due to pinion gear movement.
 

[rabbit]

I"m sure you may be insulted with this question... Are you sure you filled it with the proper amount of the appropriate gear lube?
 

[John B.]

Nisse, you"ll have to replace the crush sleeve behind the yolk. When ever replacing the seal these crush sleeves have to replaced. You"ll never get it adjusted to what it use to be.

John B.
 

[gab]

Whenever I repl. a pinion seal I center punch a spot on the pinion end, the yoke and the nut then tighten until they line up plus a hair more.
 

[nisse]

I dropped the driveshaft and it isn't too tight if anything might be loose I couldn't really feel any drag. Can't hear any noise with stethoscope or driving except for a slight clunk when braking hard at low speed.
Thanks,
John
 

[nisse]

I did run out yesterday and the parts store in town is closed on Sunday, picked some up this morning and topped it off. Only needed a couple ounces.
Thanks,
John
 

[Rex W.]

While checking the brakes on my motorhome I found the differential to be hot. The mechanic at the truck garage told me the temp. of the rearend would be about the same as the engine. I guess he was right because I've never had a problem with the rearend. It is a ford 350...
 

[Tramway Guy]

Typical temperature rise in a gearbox is up to about 100 degrees F more than ambient air....