Here is the deal. I swapped out a rear end a couple of months ago (did not change the fluid, but it was full). Truck has been running fine, but was only traveling less then 10 miles. On a recent trip 30 miles one way, all was going well until I rounded the corner of the supermarket and it seemed to jerk a little bit. I have been keeping the hubs locked so I can switch it from 2wd to 4wd easily. I went shopping and on my way home, the truck was losing power. It was pulling to the center line majorily. I really had to get home and had no cell phone, so I kept driving it as it was. About halfway home, whatever was slowing it down broke free (felt like a brake was stuck) and I could drive highway speeds again. When I got home, there was the awful smell of differential fluid. I should point out that the front passenger tire was larger than the rest (which was the reason I went to the store; to get a replacement tire). I swapped tires the next day and it seemed to drive fine. I did notice that the rear passenger brake had a steel stamping that seperates the 2 shoes had fallen down. I ended up throwing it out, since it would not stay in place anyway.
So just yesterday, I drove again 30 miles one way with no problems. On my way home 8 hours later it drove fine, but when I got out, there was that smell again. My nose does not work that well, so I cannot pinpoint the smell, but I did check the fluid in the front differential and it was low. However I unlocked the hubs yesterday, so the front diff. should not be turning. Could a bearing be overheating or something? The fluid in the transfer case was a bit low to, but there was no smell to that fluid. I am at a loss.

 

As far as I aware, used gear oil is one of the worst smelling products known to mankind.

 

i would say that since you had a bigger tire on one side of the truck and your front hubs locked you toasted something in your front diff.

 

im with tbird,
id pull the front diff cover and inspect then go from there

gl

 

Bad rear brake. Heated. Damaged axle shaft seal. Gear lube leaked onto hot brakes. Smell. Just my guess.

 

Yeah, you probably shouldn't have had the hubs locked with different size tires. My truck came with a more agressive tire on one side and an all-season on the other. They were both 31's but even that caused problems. I had to use 4WD one time (or not get home) and it was awful. I would stop and unlock the hubs and use 2WD until I got to a hill. Hope nothing really bad happened. Good luck.

 

I'm with Lazy K on the rear.....even with hubs locked and 2 different sized tires, as long as you have an open diff up front you *should* be all set with that.

Take a peek at your dust covers on the rear and prolly one of them is wet with oil.

May wanna jack up your font end and spin everything tho, just to be sure.

 

Gear Lube, and Diesel Smoke. To me, that smells like Victory. My wife thinks I'm nutz. Oh, and skunk road-kill. Roll down the winders, kids, we're Home!!!

 

'I did notice that the rear passenger brake had a steel stamping that seperates the 2 shoes had fallen down. I ended up throwing it out, since it would not stay in place anyway. '

Yeah. Spare parts. Thats what I would do.

Are ya kidding me? The 'jerking' in the parking lot was normal "locked" hubs fighting one another through the front differential. NORMAL. Throwing away brake parts, is Not.