Engine/Transmission (1998.5 - 2002) 6-speed and trans case fluids- synthetics?

[Hohn]

I have had wonderful results with REDLINE and AMSOIL synthetic fluids in the past, so I am pondering a full conversion. The engine oil and Front/Rear diffs are easy choices, but what about the trans case and NV5600??

I have been told that the trans case needs ATF. Could I use a premium ATF like Redline D4?

What about the trans? Some have said you need motor oil, but why couldn't I use Redline MTL? It has the right friction modifiers in it so the synchros work right and everything.

If you are using a premium FULL synthetic fluid (AMsoil, Redline, Neo-etc. ) in your 6 Speed and/or trans case, please reply and let me know what you using, and the results you have had.



TIA!

 

[TomGolden]

I have had Amsoil full synthetic ATF in my transfer case for about 30K miles now, and I'll probably change it within a month or so. I'll stick with the Amsoil. I have also been using Amsoil Series 3000 5W-30 full synthetic oil in my NV5600 for about 15 - 17K miles. I do engine oil analysis, but have never had any other fluids analyzed, so I don't know how things are wearing in in the differentials, transmission or transfer case, but I am not aware of any problems at all, and as far as I can speculate now, I have every intention of using the Amsoil 100% synthetic lubricants throughout my truck for as long as I own it. Truck is exactly 2 years old this month, and has just under 48K miles on it.



My personal opinions and experiences.



Tom

 

[Whitmore]

Hohn

I also have been sucessfully using the amsoil ATF in the transfer case foe about 20 K and have no problems to report, I do plan on its continued use. I want to do something with my 6 speed too so keep us informed... ... ... ... ... . Kevin

 

[n7gxz]

Hohn,



I'm running Redline MTL in both my NV5600 and NV241. I'm also running Redline 75w90 in both the front and rear diff's. So far I've not seen any problems.



Kevin

 

[Roger rodbolt]

I replaced the synthetic ATF my transfer with Mobil 1 0W30 motor oil when I built up a HD transfercase. Use Amsoil in the both Dana diff's and tryed synthetic motor oil in my NV5600 but went back to the factory oil which is also synthetic. Larry

 

[Hohn]

well...

It looks to me like I try the MTL in the nv5600, and maybe either Redline or Amsoil ATF in the trans case. I am wonderng why atf in the case, though..... What unique quality does ATF have that makes it desirable as a gear lube? Highly detergent? High temp stable? I suppose the "synchronizers" that allow shift-on-the-fly need some kind of friction, but i don't see why regular old redline MTL wouldn't work, so I am with you on using using Redline in both.

I am not sure why it is that I am so partial to Redline products. Every vehicle I have used them in has actually FELT different driving it afterward.

In addition, I would rather use a lube that's a little to heavy (high viscosity) than one that's a little too light.



Wouldn't it seem to you that MTL would be ideal in the trans case as well??



I am trying to get MAX life out of this truck-- like 20 yrs if I can.

Thanks.