Originally Posted By: deeter16317
Originally Posted By: gricker27
I need to change the rear diff oil in my 2005 dodge ram. The manual states to service the rear diff every 15K. I was going to use the Supertech 85W140 gear oil because it is $5 a quart, and the mopar 75W145 is ....... $35!!!?? Will the Supertech oil be okay for 15K? The truck sees very little towing.
Which dodge ram? A 1500 has different requirements from a 2500/3500...
Yeah, I was thinking the same thing. I would "assume" as he talked about 75W-140 he has a 1500 but you never know. I have seen people think that is used in the 2500/3500 as well.
2005 Ram 1500 = 75W-90(F) & 75W-140(R). Additive needed for LS.
2005 Ram 2500/3500 = 75W-90( F&R ). No additive needed for LS models.
To the OP. I would stick with the correct weight for whatever model you have and not experiment or alter it. 85W-140 is still a 140 weight oil so it will be ok but I would run the 75W as called for. If it is a 1500 run 75W-140. If it is a HD run 75W-90. If you have the 1500 w/ LS you will only need additive if the gear oil you buy does not already contain it. The LS in the HD's does not need any additive.
RP MaxGear works really well in the Ram axles. I have run it in 3 3rd Gen Rams and it has done great. No need for any additive with RP MaxGear as a rule( once in a while a LS axle will be a bit picky and want a little more but usually no extra is needed ). Amsoil also offers a good gear oil that generally does not need the additive. Either one should run you about $15-$16 tops and would be far superior to Supertech.
