1974 RL786LST

[Scott74]

Hi everyone,

I bought a 74 RL700L dump truck a few months ago on auction and am looking to get a little bit more info on it. I live in Colorado and use it daily to haul. It has the 10spd maxitorque transmission in it. I talked with the dealer they told me to put 80-90 gear oil in tranny. I am also putting the same weight oil in the differentials. Does the diffs require a thicker oil. I am hauling around 50k-55k gvw and changing about 4000ft in elevation. I've read on here some guys are using 85-140. Any help or suggestions is greatly appreciated. I am also looking to see where I can get a service manual for the truck. Thanks - Scott

[alex g]

In my opinion 80/90 will work fine for you

[mrsmackpaul]

Yep, as Alex and the dealer said 80/90 for the diffs, thicker oil maybe if its really hot and hauling really heavy weights for long periods and really heavy I mean over 200,000 lbs  and in 100 degree heat for 12 hours straight, but I doubt it this is your situation 

 

Paul

[Scott74]

10 hours ago, alex g said:

In my opinion 80/90 will work fine for you

 

8 hours ago, mrsmackpaul said:

Yep, as Alex and the dealer said 80/90 for the diffs, thicker oil maybe if its really hot and hauling really heavy weights for long periods and really heavy I mean over 200,000 lbs  and in 100 degree heat for 12 hours straight, but I doubt it this is your situation 

 

Paul

Thanks guys! I will continue to use 80-90 then.