Engine/Transmission (1998.5 - 2002) 80w-90 in rearend ?

[BIGDIG]

what's with this SAE 90 GL-5 gear oil in the 3500 rear axles. I went to three dealers in my area,one being a dodge truck dealer and he only had ONE qt in stock and could not sell me any from their bulk drums in shop. The others just did not stock it I have about 22ga. of 80w-90 in my own shop,I picked up that friction modifier junk ,what would happen if I changed it and put in the 80-90. I have 14,453ml. on my truck and have not had a chance to change it since I bought it . I know,I know,I know,don't say it. :{ would it hurt the gears or not until I can stock up on this rare fluid found all around the world but here



HAPPY TURKEY DAY Oo.

 

[Alan Reagan]

Good question. I changed mine and replaced with synthetic Valvoline with no friction modifier. The LSD works just fine and there is no chatter. I went with 75W-90 but the next time I'll go with the 75W-140. What you have to be careful of is the 90W having the same rating at the GL-5. If not, go synthetic and leave out the modifier until after you've driven it. I have the Dana 80 hybrid with the 4:10 like you. Synthetic is available at most parts stores.

 

[Gary - K7GLD]

at my elbow as this is typed, is 4 quarts of Amsoil 75-140 - we'll see if it lives up to the hype...

 

[jwilliams3]

80w90 is fine, just make sure to use the lsd additive.



--Justin

 

[Alan Reagan]

Gary, You may need the friction modifier with the AMSOIL. I haven't used AMSOIL so I don't know. I didn't put it in my Valvoline. Prior to my change, I had the slight shudder on turns and my LSD operation was questionable. After the change and NO modifier, the shudder disappeared. Both wheels pull when they are supposed to so I never added it.

 

[Pit Bull]

Most auto parts stores stock Mobil synthetic 75w90. Great stuff and that is all you will ever need to use. Unless you are Towing real heavy all of the time the 75w140 is way over kill and will hurt you in cold weather. Do a search, this has been discussed and the lube engineers (guys with letters behind their names) on this site have stated that the 75w90 synthetic (whatever brand you want) is the way to go.

 

[BIGDIG]

WON'T HURT A BIT

Ok so you say 80w-90 won't hurt the DANA 80 even though Dodge requires the SAE 90 GL-5 (as it says in the manual)if it is used for a short time with the fric modifier. Anyone else done this before.

 

[LSMITH]

Either use a GL5 rated oil or use a modifer that will bring the oil to a GL5 rating. Whatever you use is fine so long as it meets the spec. Personally I use Mobil 1 75-90, it works great.

 

[BIGDIG]

75-90

Ok so if I go to the 75-90 do I add the friction modifier or not. I know where I can get 5ga. buckets of that stuff. (75-90)



thanks for reply

 

[Pit Bull]

Re: 75-90

Originally posted by BIGDIG

Ok so if I go to the 75-90 do I add the friction modifier or not. I know where I can get 5ga. buckets of that stuff. (75-90)



thanks for reply

When I changed to Mobil 1 75w90 in my 2000 3500QC 4x4, the service manual said to add 3 bottles of the Mopar limited slip (smells like fish oil stuff) I added 2 bottles and mine was fine. I think all of the LSD are different and the best thing to do is add 1 bottle and then go out and do your figure 8's and see if it makes noise. If it does add somemore and keep checking by doing the figure 8's. I know it's a pain in the ass but if you just add 3 bottles you might be adding to much and eliminate the "limited" part of the "limited slip" and just be left with the slip

 

[BIGDIG]

just a thanks

Since I can't shake your hand i'll just say thanks for the help. I'll try the two bottles and take it from there. since we both have the same axles it should work.





THANKS AGAIN

 

[andrewkoperdak]

I don't believe it will hurt anything. I too would suggest the Frict Mod. I changed my fluid at 30K and put in 75W-140 from DC. I plan on towing a lot. I also towed a lot when I had 75-W90 in the rear and when I did a gear inspection I found no adverse affects of using the lower viscosity. Just my 2 and 1/3 cents worth.

R,

Andy

 

[rkressg]

I use Valvoline 80w-90 in all my vehicals. Just use the L(imited) S(lip) M(odifier) if you have a posi. Buy the 55 gal barrel from NAPA and you will be fine. Oo.

 

[RKohn]

screw the modifier...

run the synthetics. Oo.

 

[Cooker]

The Mobil 1 75w90 already has the friction modifier in it. I wouldn't add more unitl you determine you actually need it. Don't forget to do some tight figure 8's to work the oil/modifier back into the LSD. With that said, I would have a bottle on hand should you need to add a little. All LSD seems to act just a little differently.

 

[pwr2tow]

BigDig,

This is from my maintenance files;



-- 6/11/01 27,000 miles changed oil and filter,

--Changed front and rear axle fluids to Mobil 1 75-90w,

--Rotate tires.



Year and half later and now at 50,234 miles everything is o. k.

As stated earlier, do not use the friction modifier unless you have to or you will defeat the posi part of the limited slip.



Ron

 

[2-ND TIME]

diff oil

12







Have used Mobil 75w 90 for years with great seccess. TDR ran an article a few books ago and said that adding more modifier than recommended was a good idea that is what I did to a Dana 80 and am very happy with traction.



When your engine is broken in try there 5w-40 takes the cold and the heat for you southerners. Just freezing here.

 

[Gary - K7GLD]

WELL, did the Amsoil bit on the 6-speed and LS differential, no additive - drove into town for the mail - did the figure 8 bit - all seems well, but way to early to tell...

 

[Pit Bull]

Originally posted by Gary - KJ6Q

WELL, did the Amsoil bit on the 6-speed and LS differential, no additive - drove into town for the mail - did the figure 8 bit - all seems well, but way to early to tell...

Gary are you feeling like a pioneer? :-laf Others have taken the same path before

 

[Gary - K7GLD]

"Others" have gone to the moon too - but it would still be a first for ME!



Seems many of us continue our personal searches for the "perfect" lubrication solutions to meet our individual expectations - after all, proper lubrication is the life of our vehicles - the WRONG "solution" might just lead to an early death or poor operation... DC has a pretty narrow spec for the 6-speed transmission lube - and the LS differential CAN be pretty sensitive to lubes if proper LS action is to be realized... "Pioneer"? - undoubtedly not by most folks standard - but still somewhat of an "adventure" to ME...



BUT, yup - what's significant to one member is trivial to another...