It's about time to change all the fluids in my truck, actually it's past time but I'm going to do it now and I'm curious what's suggested. We have a lot of Redline stuff at work and I've had good luck with their stuff before but if the general idea is that it doesn't work with these trucks I'd like to know now.

I'm thinking:
trans/transfer case: MT90
front diff: light shockproof
rear diff: heavy shockproof

Any suggestions/comments or concerns? Anything is welcome.

 

Transfer case should be ATF+4, front dif 75w90, rear 75w90 or 75w140.

 

I just did mine today. RP Maxgear 85w140 in the rear - 5 qts, RP Synchromax in the trans. - 6 qts and Schafer 7000 15w40 in the engine. I've had the best luck with them but I wouldn't be afraid to try Redline. I use extra heavy weight in my diff. I get the least wear metal on the magnet of any gear lube I've tried and I've never seen a down side from it - not even when I lived in Co. No loss of mpg or anything else, compared to 75w90. Craig

 

Yeah I did not lose anything going to 75W140.

 

Awesome. I'll change my list to
Trans: MT90
transfer case: C+ atf
front/rear diffs: heavy shockproof (75-250 equivalent)

The heavy shockproof is a 75-250 equivalent but flows like a 75-90, or at least that's what redline says on their site. Working with the stuff I believe it, we refer to it as monkey snot it's so thick. Works really well though. It's the only thing we found that'll make our diffs live on some of the hotter tracks. The reason I went to the heavy shockproof in the front diff as well is just for simplicity.

 

75w140 is not what AAM calls for in their axels.

 

So what do they call for then. It seems that's what dodge calls for. Thanks for a completely useless post.

 

Factory spec is full synthetic 75W90 rated GL-5.

The dealer here recommended running 75W140 for people who tow heavy in hot temps.

I've run Redline 75-90 front, and 75-140 rear in the last two trucks with good results. Previous truck had the NV5600, and I ran Recline MTL in it with good results.

I run Mopar ATF+4 in the transfer case, and in my current truck's G56.

 

While we are on the topic, several people have snapped cover bolts off trying to torque them to factory spec, so I'd back that down a bit.

Also, many of these trucks have a fill line stamped on the rear diff cover which is below the fill hole. You would miss it if you didn't look for it.

Lastly, there is a magnet in the bottom of the case of the NV5600. While you are changing fluid, I'd recommend pulling a side cover off to retrieve the magnet and clean it off. RTV and thread sealant to put the cover back on.

Jeff

 

If you use these trucks like designed they all pull/work heavy.I called AAM a few years back.THEY do NOT recommend the 75w140.. in any conditions in the axels that are in Dodge trucks.Some DEALERS might.But THEY could be wrong also.Do some research and get YOUR facts straight before you call a post useless. DODGE calls for 75w140 in the COROROPTE built axels.AAM says the thicker oil dosen't dissipate heat as well. Thicker dosen't mean better.I have 75w90 Amsoil Severe gear oil in mine.I have 75w140 in my Dodge 1500 and in the differential on my Mercury Gran Marquis.THEY call for the 75w140.

 

The reason I called your post useless is because you didn't give any information and had a simple argumentative statement with nothing else. Your second post is fine and helped the topic, and I thank you for the information. My truck doesn't pull as heavy or as often as some on here but it does get used (38' 2 car trailer with plenty of other gear piled in/around the cars.)

For something like the diff cover that isn't stressed or structural I almost always just get them hand tight and have never had a problem but thanks for the heads up. I will definitely get the side cover off the trans and take a look around, not just to get the magnet but to see how things are wearing.

 

Do NOT put in MT90 !!.............. The trans takes MTL

 

Dodge calls for 75-90. Thicker is not better. Factory fill is 75-90.

 

Never said anything was better than anything else. I have been running 75w140 in the axle for 30k or so miles. Nothing has blown up yet, no noticable increase in wear...I check the plug every oil change.

 

All the fluid call outs are recommendations for what they think you/your truck will be doing. If you do something different then different fluid will work for you. For instance if someone never towed and just daily drove their truck I bet a lighter weight oil would be better because it would give them less resistance and they don't need the extra protection. I'm not saying this is me, just an example.

I just finished the changes in my truck:
75-90 in front axle
heavy shockproof in rear axle
C+ ATF in transfer case
MT90 in trans

I know it's not what some people recommend but I got the heavy shockproof and the MT90 for free. If I have any issues I'll get the suggested fluid and change it then, I've only driven a little bit but so far it shifts better. We'll see how it goes over the next few thousand miles.