I finally got around to changing diff fluid and a pinion seal that just started leaking. I had planned to do it myself but the pinion nut requires 470 ft/lbs of torque (Dana 80) and not ready to drop $$$ on a torque wrench of that range that I'll use once. So I took it to a recommended garage.

They found the gears have surface rust and the differential fluid was described as "muck". I was taken to the truck and showed this and the play throughout the gearing. He recommended an entire rebuilt rear or a used one. He didn't suggest rebuilding the gears because of the inability to ensure the rust removed from the axle housings.

My thoughts are rebuilt/used now or just refill button it up and run to failure then go with one of the first two options. The rear end has lasted this far so who knows if it will go another mile or thousands. I know it will need replacing. I feel it will let me know via noise or vibration when time has run out.

I put about 5 - 7k miles a year on the truck mostly within 50 miles of home. It's my standby vehicle. However I occasionally pull a 7000 lb trailer about 1-3 hours. Will likely curtail that.

I replaced the entire rear on my old Explorer so I know I can do it just don't feel like wrestling with something quite a bit larger.

What a day! What began as a $251 job blossomed into this nightmare. Each time I replace an unusual part or find dirt packed into the deep dark recesses I ask "What in the #!@& did the previous owner do to this truck?

Thanks,

Reg

 

I doubt if there is any rust where the ring and pinion make contact. That would be the important area to view to see if it is chewed up.
I think you should have the rear end refilled and see what happens. I wonder if it was in deep water and got water inside sometime ago.
If you can move your pinion side to side or top to bottom where the drive shaft hooks on a new seal may have limited success and may need pinion bearing service. Well those are my thoughts on it.

 

X2. Better advice than you got from the garage.

 

Per shop there is rust on pinion to ring gear surfaces and play in pinion. Rebuilt Jasper rear is $4125 w/ 3 year 100k mile warranty. Used is $2985 w/100 day warranty.

Neither of those choices is going to happen today. My plan is to replace the seal which is leaking replace the bearing to protect the seal fill it up and drive it.

 

Marching orders have been given to the shop. Pinion bearing and seal to be replaced. $750! Better than $3000. Truck will become limited use vehicle not that it is driven very much now.

I asked the shop foreman if he had any concerns with differential reliability in terms of truck usage. His one concern was about the two outer bearings that receive the axle ends since he can't see those to inspect them. I'm hoping that I can replace those and rebuild the rear farther down the line.

Anyone want to buy a truck? It has very loud horns and a really big bumper.

Thanks for the feedback.

 

It might be a good idea to replace the fluid in your rear axle again after using it for a while, like after some extended highway driving to get the new mixed with what was left in the rear end after draining it.
If your truck got water in the rear axle, it would be a good idea to check the fluid condition in the front axle too, in case it also got water in it. And then only drain it if it got contaminated too. I kinda hate to mention this stuff but it may be the best to do. Patrick

 

That's my plan. This change is a flush. Will change again later and replace what bearings and gears I can. I let them do the pinion stuff as it read like a real PITA.

470 ft/lbs for the pinion nut! I thought the truck was coming off the jack stands when I torqued the pitman nut with 225 ft/lbs.

 

I signed a release of liability for the garage since the owner won't be responsible for new parts with the rear in the shape it is. That is not replacing everything. The good news is with the release the shop manager called me last week to come in to look at the carrier bearings.

The rollers and race are heavily pitted and it didn't take a genius to see that they require replacing. As for the pinion yoke they will press a sleeve onto it due to damage there. He states it is a common repair for the yoke.

The pinion itself is in good shape as in no surface rust or pitting. The ring gear has pitting on the outer half of the teeth and since the two must be replaced as a pair the ring will stay as is. The rear end is robust enough that I won't worry about catastrophic failure. Noise and vibration will say when further attention is needed.

I asked about how the differential is held in place with the axles out and he said funny you should mention that. Normal it is held firmly in place however mine was easily removed by hand. This may mean wear in the housing itself. As I was leaving I asked again about this and he feels shimming will eliminate the play.

New price about $1100. I make enough that I'm going to pay to have someone else with the tools, time and skill deal with this.

Reg