Driveline fluid recs for '08 Ram 6spd?

[opposite_locker]

Will soon be time for another change of all the driveline fluids. Truck is an '08 Ram 4.7L 4x4 with ~120k miles, Getrag 238 6spd transmission, and open f&r differentials.

Factory specs:
G238 trans - ATF+4
transfer case - ATF+4
front diff - 80w90
rear 9.25 diff - 75w140

What I have been running, at 60k intervals under severe service:

G238 trans - Redline C+ ATF (1st change), Redline D4 ATF (2nd change)
transfer case - Redline C+ ATF (1st change), Redline D4 ATF (2nd change)
front diff - Redline 75w90
rear diff - Redline 75w140

Figured that a manual trans & transfer case wouldn't require the extra friction modifier in ATF+4, hence the change to D4 ATF 2nd time around.

I would like to extend drain intervals to the 80k-100k mile range, and this is under all types of severe service. Think the Redline would be able to go the distance, or am I better off with a different oil?

 

[ac_tc]

Just keep on...

 

[bullwinkle]

Why not ATF+4? Every ATF+4 is a FULL SYNTHETIC ATF! That said, I run RP in my Ram rear diff & my wife's xB transaxle, and putting RL D4 in my '89 ZF in the F-450-just can't see wasting the money when ATF+4 is a Full Synthetic & the Mopar spec fluid in the 48RE & transfer case on the Ram.

 

[unDummy]

Severe service, shorten the interval and keep on driving or prove your interval with a used oil analysis.
Whether you use D4 or C+ is irrelevant. But, I'd wonder how both would react to a thicker fluid or blend. MTL might even be an option if you have warm enough weather for it.

Only a used oil analysis can assist you in determining interval.

Not everyone cares to use an OE fluid. I almost always don't as there are usually better options.

 

[opposite_locker]

Quote:
Just keep on...


Might just end up doing that. Current 60k intervals with Redline seem to be working just fine

Quote:
hy not ATF+4? Every ATF+4 is a FULL SYNTHETIC ATF!


You sure about that? Everything I have read stated that ATF+4 is a synthetic blend, and can only be so with the appropriate friction modifiers in order to be labeled as an ATF+4. I believe this is also why there aren't any full-synthetic ATF+4's available (ie from Mobil 1, RP, Redline, Amsoil, etc...though they do rate otherwise-labeled ATF's as acceptable in ATF+4 applications)

Regardless, there is no way I would trust any ATF+4 with 60k intervals under the conditions my truck sees.

Quote:
Severe service, shorten the interval and keep on driving or prove your interval with a used oil analysis.
Whether you use D4 or C+ is irrelevant. But, I'd wonder how both would react to a thicker fluid or blend. MTL might even be an option if you have warm enough weather for it.

Only a used oil analysis can assist you in determining interval.


I see no reason to shorten the interval as the current regime seems to be working just fine. But I would love to only have to change my driveline fluids once every 2 yrs (approx 80k-90k miles) during downtime in the winter. The trans, t-case, and front diff shouldn't be any problem. Only the rear 9.25 differential is known to be hard on gear oils, but usually that is the case with the factory trak-lock limited-slip differentials. Have been told that the open 9.25 rear is much easier on gear oil...but then again, not sure how reliable the source of this information was.

Are there any used oil analysis out there of an open (non-LSD) Chysler 9.25?

I have also thought about trying a manual transmission fluid. The G238 trans has been shifting great cold & hot on both RL ATF's, but I've always wondered if using MTL, MT90, or a mixture would be more appropriate. Will probably stick with one of the ATF's for now, unless I come across a compelling reason to switch.

 

[dave1251]

Originally Posted By: opposite_locker
Quote:
Just keep on...


Might just end up doing that. Current 60k intervals with Redline seem to be working just fine

Quote:
hy not ATF+4? Every ATF+4 is a FULL SYNTHETIC ATF!


You sure about that? Everything I have read stated that ATF+4 is a synthetic blend, and can only be so with the appropriate friction modifiers in order to be labeled as an ATF+4. I believe this is also why there aren't any full-synthetic ATF+4's available (ie from Mobil 1, RP, Redline, Amsoil, etc...though they do rate otherwise-labeled ATF's as acceptable in ATF+4 applications)


Regardless, there is no way I would trust any ATF+4 with 60k intervals under the conditions my truck sees.

Quote:
Severe service, shorten the interval and keep on driving or prove your interval with a used oil analysis.
Whether you use D4 or C+ is irrelevant. But, I'd wonder how both would react to a thicker fluid or blend. MTL might even be an option if you have warm enough weather for it.

Only a used oil analysis can assist you in determining interval.


I see no reason to shorten the interval as the current regime seems to be working just fine. But I would love to only have to change my driveline fluids once every 2 yrs (approx 80k-90k miles) during downtime in the winter. The trans, t-case, and front diff shouldn't be any problem. Only the rear 9.25 differential is known to be hard on gear oils, but usually that is the case with the factory trak-lock limited-slip differentials. Have been told that the open 9.25 rear is much easier on gear oil...but then again, not sure how reliable the source of this information was.

Are there any used oil analysis out there of an open (non-LSD) Chysler 9.25?

I have also thought about trying a manual transmission fluid. The G238 trans has been shifting great cold & hot on both RL ATF's, but I've always wondered if using MTL, MT90, or a mixture would be more appropriate. Will probably stick with one of the ATF's for now, unless I come across a compelling reason to switch.



It is a group III basestock. http://www.allpar.com/mopar/transmissions/fluids.html
http://www.imakenews.com/lng/e_article000441933.cfm?x=b5q0KFl,b2Wdmnq1

The reason why EOM, RP, Redline, Amsoil can only use group III basestocks and a lubrizol additive package to be an offical ATF+4 fluid. This is a very good ATF on the market if I still had my Dodge I would use it.

 

[AzFireGuy79]

I agree that for what it is(group III) ATF+4 is a great OEM fluid. Redline C+, in my opinion is much better being a largely Group V base oil. FWIW, Redline uses Lubrizol. Their co founder worked there for many years(Roy Howell) and is considered by many to be a genius. Redline does not offer any Group III oils. FACT. Not saying you stated as such, just clearing it up for anyone wondering.

To the OP. I would stick to what you are doing. If you want to extend the OCI, get a used oil analysis to build confidence in your plans to extend out a bit further. No need to go backwards by going back to ATF+4. Sounds like you are happy with the current fill. Stick with it.

 

[opposite_locker]

Didn't realize ATF+4 was a GRP III oil. Would consider using it in less demanding application, but going to stick with a premium oil in this instance.

Talked to Dave at Redline today...he was also of the opinion that it didn't matter which ATF (C+ or D4) I used in the manual trans & t-case.

Going to stick with Redline throughout and 1.5 yr (~60k) intervals.