Royal Purple

[RJOL]

Time to change the drive train oils in my 2005 3500. I have the G56 transmission and 4X4 differentials. I'm going to use regular ATF+4 for the transfer case; Royal Purple Max Gear 75-90W synthetic for the differentials; Royal Purple Syncro Max for the G56. Anyone got a good mail order site for Royal Purple? I'm not interested in an "oil war. " Just a good site for the above... I might change out the coolant too, so any suggestions there would be appreciated...

 

[blacksheepdiesel]

Some auto parts stores carry it or will order it for you. O'Reilly's stocks some RP.

Godspeed,
Trent

 

[AH64ID]

Are you sure about syncro max for the G56? They are specked for ATF.

 

[mberry]

Several of our local NAPA auto parts stores stock RP. Also, Summit Racing stocks it as well. I don't know about the coolant, so please share what you find out since I need to change my coolant as well.

 

[MA2LA]

I used the 90-140 in my rear and the atf max for trams and t/c. I order it in 5gal bulk from a local custom shop witch is nice. once i get my pybass filter i will switch to thier oil of my engine

 

[AH64ID]

For the rear end AAM has stated that 75w-90 is all that is required unless you consistently above GCWR towing thru death valley... I am sure a 75-140 wont hurt anything but fuel mileage... but its not necessary.

 

[steved]

I am sure a 75-140 wont hurt anything but fuel mileage...

Even 85w140 RP won't hurt mileage... I've ran it for better than 100k, and posted some very nice mileage numbers (numbers better than a lot of owners get).



FWIW, the RP Synchromax bottle states it can be used in manual boxes calling for ATF... I ran it for a long time in my tcase, but it was horrible in my NV5600. I believe from what I remember, Synchromax is the thinnest of the synchromesh-type fluids (when compared to Redline MTL and Amsoil MTF).

 

[AH64ID]

Those fluids are pretty thin to start with, as gear lubes go. . 5w-30 is what Amsoil MTF is.

 

[pullya]

You can get your coolant at the dealer. It is a special coolant and it should be mixed with distilled water. You can also use Zerex G05 Hoat coolant mixed with distilled water. I think it holds about 7 3/4 gallon total. The Zerex is the same as the factory G05 Hoat.

Jay