I have a 1995 Dodge ram 1500 4x4 with a 5.9L engine. I recently started having problems with my rear end binding while turning.. or towing my boat. I pulled the rear cover plug and noticed metal shavings and dark fluid. My REAL question is.. How do I deciper the Axle size? I know its a 3.55 ratio. But the dealer wouldn't tell me anything else besides that. I know they just don't want to give away free information. I'm thinking its a 9 1/4 Ring with 3.55 gears. But I just wanted a second opinion on it. And also, since my posi seems to be binding up on me on turns.. is it safe to say that its junk? Or can it be cleaned out and reused? I would prefer to rebuild the axle that is in it.. But if a junkyard swap is a better choice.. I'll do it. Thank you.

 

Yep, 9.25 rear. If you have posi, drain all the fluid, clean it out nice, refill with fresh fluid, and the Friction modifier that is required for clutch-type posi.... probably fix it right up for ya. At least, for a while.

 

I had a rear end lock on an old Van of mine and destroy the planetary in my transmission in the process.
These 9.25's are infamous for thier somewhat weak pinion bearings, and if what you saw are shiny metal shavings, I'd be checking the pinion for play before slapping it back together.
If the pinion has taken a poop and galled the gear in the process, I'd consider a junkyard rear as a cheap fix for now. Plan on pulling the diff cover before buying or shove a magnetic retrieval tool in the filler plug and see what you pull out. The problem is finding a good low mile diff.
BTW 2000 and up use a different brake system which is adaptable.

 

Thanks. What are your suggestions for rear diff fluid? Mitchell tells me I can use 80-90, 80-140, or even 75-90. I think the axle is a little more specific than that. I was thinkin thicker the better. I don't know the loopholes around Dodge. I'm a Chevy mechanic. lol

 

I just use 80-90, and call it good. (don't forget the friction additive.)

 

since you have a 4x4 and might want to change the front too, walmart has gear oil in a gallon jug for the very reasonable price of about $12-13/gal. they have an 80-90 and a 75-140.

don't forget the friction modifier for your posi.

 

Hotter climate or heavy work conditions, use 75w140

Cooler or light work duty, use the 80w90.