2nd Gen Non-Engine/Transmission Diff fluid change, potential probs ?

[JPLB22]

I have just completed my first diff fluid change. The dealership has done it once already but this is my first time doing it. I have two ( most likely stupid ) questions.



I think I may have been a little too excited with the RTV, and used too much. I was very concerned with making a good seal. Is there any potential problems with using too much RTV?? If I used too much and some squished into the inside of the diff housing could it cause any problems if it was floating around in there??



And also for anyone who does there own diff fluid changes, how much fluid did you put in to yours?? I have a Dana 60 front and a 70 rear.



TIA



Jeff

 

[illflem]

I wouldn't worry about too much RTV, just don't do it next time.

I guess it's remotely possible for a chunk to come off, get ground up in the gears and bearings then get under a seal causing it to leak.

I'm not sure how much fluid they take since I pump mine from a 5 gallon tub, but one thing I've found out the hard way on several rigs is to heed the level recommended by your owners manual. When I've filled the differentials to the bottom of the fill hole or on a non level surface oil has leaked out of the end of the axle making a mess of the wheels and brake pads and/or shoes.

Not sure what the manual on your truck recommends but on older rigs they say 3/4'' below the fill hole in the rear end and 1/2'' below on the front. Some folks here have suggested jacking the truck on one side to get more in -bad advice- experience has taught me they will then leak.

 

[JPLB22]

illflem



If they do happen to leak out the ends of the axles do you just let it drain what ever it needs to, and just drive it normaly? I put in a little more than what is recomended because I swabbed out the bottom of the diff housing to get all of the fluid out and when I filled the recomended amount I could not feel the fluid in there with my finger. I filled until it ran out of the fill hole.



Also would it be a problem to mix Castrol sae 75 - 90 with Mopar 75 - 90.



I know not to sweat the little things, but I am a first timer with a lot of these things and the truck ain't cheap. So I worry a little.



Thanks Bill



Jeff

 

[Pit Bull]

I did my 2000 and filled it till it ran out the fill hole and never had a leak. Most of the gear lubes say they are compatible even synthetic with dino. Drive it.

 

[illflem]

Jeff, the owner of a '97 that I filled all the way to the bottom of the fill hole noticed an oil leak out of his drivers side front axle end after just a 7 mile drive home. Painted his wheelwell with oil. That's when I finally read about the recommended level in the manual after the owner pointed it out to me. I'd been filling differentials to the bottom of the hole for years, guess it was a bad habit. I pumped the excess out, almost a quart extra in that 1/2'', no more leak. This was the last time I've overfilled one.



Long before that I had a crack in my own 4wd actuator that allowed water in, had to change the fluid several times to get the water out. It would always leak out the axle ends or puke out the vent tube afterwards till the fluid went down to the recommended level. Unfortunately I never put 2 and 2 together.

Personally I would suck out any extra if your manual indeed says the correct level is below the hole. It's a hassle, don't know why they didn't just put the plug where the hole bottom is the correct level.



It's not recommended to mix brands of oil but we've all probably done it. Once again it's probably ok, just not a good habit.