Diffy Flewid Cervice

I'm not sure what is in there now, but I am sure its been neglected.

I am thinking Royal Purple perhaps (summit has it for $9.95/qt). Ouch!!! need four to service front and rear. This is going to be a little expensive. Guess I will get some new gaskets before I find that I ruin one in the process.

Anyhow onto gear oil weight choice. Manual states specs are 75w90, or 80W140 with towing package. Please don't laugh at me, but I really don't know axles I have although I know this wag had the little draw bar dinky hitch on when I picked it up...which I promptly removed the next day.

Have you guys used any other gear oil weights in your wags, RP sells an 85W140 and a 75W140 too.

I don't tow, although it will become an option when I find a real class II or III hitch I can salvage from the local pick and pull where I can actually get the bolts loose. Grnt!!!

BTW is Royal Purple overkill at this price? I hear it doesn't dilute with water (according to "Trucks")

[joe]

I've never used Royal Purple so I can't comment. Redline is my favorite in syn lube and no syn gear lube is cheap. The factory recommend gear lube weights are just fine. It's unlikely in a late GW to find a LSD unit but check the rear diff for any tags the read something like "warning a LSD friction modifier additive is needed". If I remember right though most if not all syn gear lubes are LSD compatible so no need for the additive. In any case read the tag if any and read the lube bottle.

Originally Posted by -joe

I've never used Royal Purple so I can't comment. Redline is my favorite in syn lube and no syn gear lube is cheap. The factory recommend gear lube weights are just fine. It's unlikely in a late GW to find a LSD unit but check the rear diff for any tags the read something like "warning a LSD friction modifier additive is needed". If I remember right though most if not all syn gear lubes are LSD compatible so no need for the additive. In any case read the tag if any and read the lube bottle.

I've used redline in the past, perhaps I should give them a look see this run.

yeah the RP syn does have the additive in it. I can guess from snow and wheeling response I have an open rear axle.

Thanks, will stick with the standard weight.

[Serious Johnson]

Yeah, the weight recommendations in the manual are not so much for the physical properties of the diff, as for the intended use. Redline contains limited-slip friction modifier, except in the "NS" (Non-Sulfer) range.

S.J.

Originally Posted by Serious Johnson

Yeah, the weight recommendations in the manual are not so much for the physical properties of the diff, as for the intended use. Redline contains limited-slip friction modifier, except in the "NS" (Non-Sulfer) range.

S.J.

Thanks, I see that now as I looked. Seems the price is the same @ summit despite NS (no friction modifier) between the choices (7.95, maybe I will go with redline to save a few bills).

Am I correct in saying that it doesn't hurt to put a syn gear oil with the addtive already in it in an open non-locking diff? Maybe it will be less efficient, if that's the case my mind is made up, all RP has the additive, redline you can get with and without which is nice....

[710 Burner]

Originally Posted by -joe

... It's unlikely in a late GW to find a LSD unit but check the rear diff for any tags the read something like "warning a LSD friction modifier additive is needed".

Not so unlikely. I have one. I am running Castrol synthetic gear lube.

[joe]

Originally Posted by Jeepeta

Am I correct in saying that it doesn't hurt to put a syn gear oil with the addtive already in it in an open non-locking diff?

Correct.

[TexTJ209]

Switching to royal purple raised my gas mileage from 8mpg to 13mpg in my TJ. But Im pretty sure thats because my previous fluid had the consistency of thick gravy.

Originally Posted by TexTJ209

Switching to royal purple raised my gas mileage from 8mpg to 13mpg in my TJ. But Im pretty sure thats because my previous fluid had the consistency of thick gravy.

Man I hope I can expect that sorta response from Jeepeta. She's been sucking gas like a ....... well just let me say its been very thirsty for gas these days 8-9 mixed hwy and city. Did the transmission wed, and already seems better. I hope the diffy service really helps. The rear sound just a little noisy but that could be just in my head.

Originally Posted by Valdez Explorer

Not so unlikely. I have one. I am running Castrol synthetic gear lube.

so do you have the tag, how did you tell from the outside?

[bchesley]

I use RP in my heavy duty dodge and will never use anything else. I dont have it in my jeep yet because I am going to be diong a gear swap and lockers soon. It is good stuff!!!!!!

Brad

[chr1s]

I hope all this work means you are planning on going to the Jeep event at Wharton State Park NJ in June and the Jeep Show in York in July...


hope you left me some good stuff @ shorties !?!?!?

[FSJeeper]

Originally Posted by bchesley

I use RP in my heavy duty dodge and will never use anything else. I dont have it in my jeep yet because I am going to be diong a gear swap and lockers soon. It is good stuff!!!!!!

Brad

Yep, changed the diff fluid to RP in my new Dodge 3500 at 500 miles as recomended by the TDR. Apparently the new axles in the new Dodges need synthetic very early in life or they have issues.

Anyway, no issues what so ever but no mileage gains that I can tell.

[mechanical man]

Changing differential fluid making mileage to go from 8 to 13 mpg. Impossible!!!!!

Originally Posted by chr1s

I hope all this work means you are planning on going to the Jeep event at Wharton State Park NJ in June and the Jeep Show in York in July...


hope you left me some good stuff @ shorties !?!?!?

I am going to try for Wharton, probably depends on if I start the paint job prep early, so yeah I probably will be able to go.

Shorties is fairly picked over honestly right now.

[TexTJ209]

Originally Posted by mechanical man

Changing differential fluid making mileage to go from 8 to 13 mpg. Impossible!!!!!

If you'd read the rest, it was because my diff fluid was basically thick soup(water and oil don't live together happily ever after). I tested it before AND after, otherwise I wouldn't have believed it either. Probably some other factor involved, but I've got no idea..

Hey one last call for help guys...

Can anybody recommend a good source for gaskets. I'm close to placing and order on rockauto.com, but don't know if those are cork gaskets or something chitty like that. Would like to get something good actually that doesn't leak if I am putting expensive gear oil in.

Advice appreciated.

[TexTJ209]

Originally Posted by Jeepeta

Hey one last call for help guys...

Can anybody recommend a good source for gaskets. I'm close to placing and order on rockauto.com, but don't know if those are cork gaskets or something chitty like that. Would like to get something good actually that doesn't leak if I am putting expensive gear oil in.

Advice appreciated.

Look into the Lubelocker Gaskets, they sell 'em on lots of 4x4 sites.

Thanks, those lube lockers look awesome. Since I can get Mr. Gasket from Summit, I am going to get them instead and see how they work. They are something better than cork, so we'll see.

I forgot about the transfer case. Manual states auto trans fluid, but dextron II, couldn't I use DIII or DIV instead. Why do they say D3 for transmissiong and D2 for transfer case.

Better yet, what are you guys putting in your t-cases?

[joe]

Originally Posted by Jeepeta

I forgot about the transfer case. Manual states auto trans fluid, but dextron II, couldn't I use DIII or DIV instead. Why do they say D3 for transmissiong and D2 for transfer case.

Prolly just haven't updated the tcase page in years. Dex III, IV are just later versions of Dex II which I don't think you can even get anymore unless some McParts house has some dusty ones on a back shelf. The later versions work fine in anything originally using Dex II.