Dana 44 which gear oil?....one more time!

[ryan2022]

Hi guys, Ive searched through the site, and visited BITOG, AND called the dealer...AND visited the local part store....AND read the owners manual...AND the shop manual.

They all seem to have different views on gear oil. I have an '05 TJ with a Dana 44 rear end, with the LSD and tow package.

I wont be doing any heavy towing at all, and might do the odd light off road session, but no major stuff. the jeep will mostly be used for road.

The dealer looked up my VIN# and said it should have 75w140 front and rear with LSD additive in the back. The manual says 80w90 OR 75w140 if youre towing. Should I go with the 140W seeing how it came from chrysler?

I bought some Lucas 75w90 synthetic with extra friction modifier today, and I'm second guessing myself. I've heard the Rubicon needs 75-140, is there rear diff any different from mine?

Please help. I dont want to cause any damage!

I know its been covered, its just so hard to find a clear answer in the previous posts.

Ryan

[Jerry Bransford]

Extra friction modifier should not be added as that can cause the gears to run hotter and the LSD to chatter. The exact viscosity of the GL-5 gear lube is not as important as it being rated GL-5 or GL-6. If you live in a colder climate, choose a lower viscosity like 70W-80, 75W-90, 90, etc. If you tow, wheel in very tough environments or it gets very hot, a higher viscosity like 80W-120, 80W-140 etc. is recommended.

Personally, I now believe in using a non-synthetic gear lube for my axles with recent revelations that the gears run cooler in a non-synthetic gear lube than the do in a synthetic gear lube. That's probably not a big deal if you don't wheel in tough conditions but if you do...

P.S. Unless it was added later, your TJ doesn't have 3.55 gearing in your axles as indicated in your profile. 3.55 was only available in the '97 TJ. Since you have a Dana 44, your axle ratio is actually a 3.73.

[neZZr]

It seems you answered your own question. When in doubt, use the FSM.

The Rubicon does require 75w140 in the rear, but does NOT require limited slip additive as the LSD is a gear based unit, not clutch based. The front axle is okay with 80w90, but since you have the tow package, I'd use 75w140 in case you ever tow something.

Here is a snip from the FSM:
AXLE LUBRICATION
NOTE: DiamlerChrysler recommends using Mopar® lubricants or lubricants of equal quality.

FRONT AXLE
181 FBI (Model 30) - Mopar® Gear Lubricant 80W-90 (Trailer Towing Mopar® Synthetic Gear Lubricant 75W-140)
RUBICON 216 FBI (Model 44) - Mopar® Gear Lubricant 80W-90 (Trailer Towing Mopar® Synthetic Gear Lubricant 75W-140)
REAR AXLE
194 RBI (Model 35) - Mopar® Gear Lubricant 80W-90 (Trailer Towing Mopar® Synthetic Gear Lubricant 75W-140)
194 RBI (Model 35) 4.56 Ratio - 2.4 L Enigne and 42 RLE Automatic Transmission - Mopar® Synthetic Gear Lubricant 75W-140
226 RBI (Model 44) - Mopar® Gear Lubricant 80W-90 (Trailer Towing Mopar® Synthetic Gear Lubricant 75W-140)
RUBICON 226 RBI (Model 44) - Mopar® Synthetic Gear Lubricant 75W-140
NOTE: Trac-lok® equipped axles require 118 ml (4 ounces) of Limited Slip Additive in the lubricant.

[ryan2022]

So I take it, theres nothing different in the rear diff when you have the tow package? Thats what had me messed up.


Thanks a lot guys, I ended up digging a bit of info on it, so sorry for the repost. I know its been covered 100 x.

Jerry, I was wrong when I filled that out. I had my numbers mixed up. I just saw the post telling people to fill out their profiles and I through it in there.

I'm up in canada, and we see the odd -30 day in the winter. I might go with the 75w90 that I picked up.

I really dont see doing any towing, we'd probably use the hitch for a bike carrier before we'd tow anything heavier than a small utility trailer. If I ever did any light towing, Id probably dump the fluid after. ...just parranoid.

Thanks for the help.

ryan

[jeepinuvalde]

Hey guys, I didn't want to start another thread on this so i'll just ask my question here. Sorry to hijack.

I just changed my gear oil and I opted to use 1 quart of Rotella 80-90 and 1 quart of Lucas oil stabilizer. I know the Rotella is the right grade, and upon reading the bottle of Lucas it says it's safe for differentials. Lucas recommends 50-100% use of it's product. It also states that no additives are needed for limited slips. Was my choice okay, or am I doing damage to my rear end? I have an 06' Unlimited Dana 44 3.73, with the traclok. BTW I don't think I have a towing package if there was ever one. My Jeep does not have a receiver.

[Jerry Bransford]

If it were my gear lube, I wouldn't have added that Lucas oil stabilizer to the gear lube. First, gear lubes are careful blends of all kinds of ingredients and most additives simply disrupt that. Plus there was a very convincing video that used to be on Bobtheoilguy's website that showed what happens to a good quality gear lube after Lucas Oil Stabilizer was added. The gear lube quickly turned brown after the gears started picking up the gear lube from all the air that was being added to the gear lube after the Lucas was added.

I'm a firm believer in not adding aftermarket additives to my gear lubes, ATFs, or engine oils. Even the manufacturers of those lubes caution against adding aftermarket additives to them.

[jeepinuvalde]

I was reading the post by neZZr, and he said that our limited slips are gear based not clutch based, I guess that makes sense. When I was looking at my gears, my carrier contained what appeared to be normal spider gears. The only thing that I disagree with neZZr is that the tag on my coverplate said 60 oz. of 80-90 + 4 oz. BTW my LJ is an 06' and the diff cover had what appeared to be a date stamped on it, 032000 (march 20 2000) right? I guess i'll take your advice Mr. Bransford and change my oil again. I'll just go ahead and use two bottles of Rotella 80-90. I'll be doing this friday, I hope my gears don't mess up by then.

[Wheelin98TJ]

Originally Posted by jeepinuvalde

I was reading the post by neZZr, and he said that our limited slips are gear based not clutch based, I guess that makes sense. When I was looking at my gears, my carrier contained what appeared to be normal spider gears. The only thing that I disagree with neZZr is that the tag on my coverplate said 60 oz. of 80-90 + 4 oz. BTW my LJ is an 06' and the diff cover had what appeared to be a date stamped on it, 032000 (march 20 2000) right? I guess i'll take your advice Mr. Bransford and change my oil again. I'll just go ahead and use two bottles of Rotella 80-90. I'll be doing this friday, I hope my gears don't mess up by then.

The gear driven limited slips are only in Rubicon models in the rear axle.

Your LJ has a Trac Lok limited slip which does have clutches.

You need the friction modifier for your diff.

[neZZr]

I must have dozed off there, I could have sworn you said you had a Rubicon

Your coverplate said 80-90 because that is what the D44 is designed for. The FSM just recommends the 75-140 because it is synthetic... the factories like synthetic for any hard-use scenarios like towing. Mopar only sells two GL-5 axle lubes to the dealers... 80-90 mineral oil, and 75-140 synthetic... so that's what they put in the FSM.

Although your Jeep has the tow package, which calls for synthetic in the FSM, it was probably likely filled with 90-90 from the factory. That's proven by the tag you found. In reality either one is fine, and if Jerry is correct 80-90 may in fact be better.

[ryan2022]

Just to bring this back from the dead.

I ended up swapping in the old gunk for 75w90 synthetic with small amount of lsd additive to be safe.

The jeep feels much more "lively" and fuel mileage is up at LEAST .0002 mpg!

All joking aside, I think it is better on gas, and doesnt feel like its dragging its butt.

Thanks for the recommendation guys!

[rutacon05]

i'm reviving this thread, i had similar questions about my diff in the rear of my rubicon.

so the factory wants 75w140 if you are towing (i installed a 2" reciever)

or 80w90

the rubicon models don't need limited slip additive because they are gear based (what my brother said looked like a torsen design)

so just to be safe i'm gonna change my fluid with 75w140 front and rear. i was thinking AMSOIL but i might just pick stuff up from the dealer to be safe. also with unit bearing hub design the front spins as much as the rear does just with out load on it until you actually engage 4wd right?

[76silvercj5]

I am changing my diff fluids this weekend. Finally got some new diff covers and I wanted to check if I had it right before I start. I read on the forum tj bootcamp the recommended fluids and fill amounts for my axles. My rear is a dana44 with a Detroit trulock do I need to add an anything extra. Also with lift I have do I still make sure that I am able to stick my finer in and feel oil? I guess I want to make sure I don't over/underfill the diff.
Thanks

[Jerry Bransford]

A Detroit Locker requires no additives, any GL-5 or GL-6 gear lube is fine. Fill it to the bottom of the fill hole. Not sure what a Detroit Truelock is, I just went by your signature when I referred to a Detroit Locker.

[rutacon05]

like i said my brother and i were curious as to what type of limited slip is in the rear of the rubicon, when he saw pictures he said it looked like a torsen type, sorry i misspelled it. looking it up it's a torque sensing differential or helical differential where no clutch packs are used, so technically it's not a limited slip, weird i know. What does a Torsen limited-slip differential do? | Answerbag.com

[rutacon05]

i just called the dealer 30 bucks a quart for the 75w140! sheesh!