Anyone have any recommendations for changing the rear pinion bearing on an 04 F250? My pinion seal was leaking so I changed it out. I did not put in a new crush ring, I measured the position of the nut before taking it off and went back to the exact position when I put the yoke back on with the new seal. Shortly after I started getting a howl in the rear end. I jacked up the truck and let it idle in gear and listened to the rear end with a stethoscope and it sounds like the noise is coming from the pinion bearing. Can the pinion bearing be changed without pulling the chunk out. If so how do I know how much torque to put back on the nut?

 

What is this chunk you speak of? Do you mean the carrier? New pinion bearing means removing the old bearing from the pinion (good bearing puller and/or press) and removing the old bearing race (brass drift, dead blow). The new race has to be driven into place in the housing and new bearing has to be pressed on the pinion. A new crush sleeve should be used and tightened until the proper bearing pre-load is reached, there is not a torque spec. You should also re-check your wear pattern, since the new bearing may be slightly different (a few thousandths matter). I recommend you take it to someone who does differential work on a regular basis and provides a warranty.

This is why I always recommend AGAINST the method of marking the nut and putting it back in the same place. There is no way to get the bearing pre-load correct other than shear luck. Now, the crush sleeve can be re-used, but it is best to add a small shim and crush it a little more, or at least tighten the nut and check the bearing pre-load to make sure you reach the correct spec.

 

counting threads is not how its done, one should check preload

 

What should it cost approximately to get a pinion bearing replaced? I called one shop and he quoted around $2100. He said he would not change the pinion bearing and warranty without rebuilding the whole differential. That sounds a bit steep, Jeeze, LOL. Hell I am trying to recover from changing my HPOP, Oil cooler, EGR Cooler delete, IPR and ICP sensor last week.

 

well about $1000 in labor here. then add parts.

 

You should be able to find a shop for under $500.

 

Cheezit, how many hours do you quote for that job? Just curious...

 

8-10 hours. but if you want it done right vs slamed together theres a differnece in pricing.

 

I heard an interesting take on differential oils this morning. I brought my truck into a local differential shop this morning to get my pinion bearing done. Small shop, but he does a ton of differential work and comes highly recommended. He ordered a kit for my truck and will changne the carrier bearings and pinion bearing while he is in there. This guy said he would "NOT" put synthetic oil back in my rear end. He said if I wanted to put synthetic oil back in my rear end he would not warranty his work. He claims that synthetics are not good for roller type bearings. He says that the oil does not stick to the bearings and gears as well as non synthetic and does not provide the cushion that non-synthetic provides for roller bearing. He said he changes out a lot more bearings these days since the start of using synthetic oil in newer trucks. He said that the places where he orders parts from recommend non-synthetic oil as well for the same reasons. I am just wondering if any one else has encountered this opinion. It makes sense and the guy seems very educated on the subject, but I am a bit skeptical. Hell I even have four bottles in my truck of mobile one synthetic 75W-140 and he said "please do not make me put that back in your truck". He has been building rear-ends for over 20 years.

 

I can't comment on all differentials, however, even the owners manual says to use synthetic on the Sterling 10.5 diffs. I also used M1 75w-140 on my rear diff.

 

There's lots of high mile differentials running synthetic. I think what could be the cause of the mechanic's thoughts is the synthetics have a much longer service interval, so if you aren't checking it and your fluid gets water/contaminants in it, it will be running longer contaminated versus a conventional oil that gets changed out every 20k. I'll be sticking with synthetics.