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Preferred fluid/lube for G56 ?

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'05 Budget Engine Rebuild

Im getting ready to change out the SBC Con OFE clutch on my 2005 to a Valair organic DD and will need to change the G56 transmission fluid as well.

Ive been running Trans Coolers and an extra quart of Mobil Delvac 50 for the last 50k, but what is the preferred lube or combination of fluids for the G56 that will help keep it running COOL and QUIET ??

TIA
 
After I ditched the DMF, I ran the Delvac 50 for several years. It was a real pain to shift any time it got cold, so the next time I changed it, I went with Red Line MTL 75W/80. It is just as quiet as the Delvac, and shifts so much better when cold, even when it's well below zero.
 
Also, it seems to run cooler than the Delvac. I don't have a temp probe installed, but while towing, I could feel quite a bit of heat on the shifter itself. With the MTL, it still gets warm, but nothing like before. Not scientific at all, but I'm guessing about 15-20° cooler based on feel.
 
From my research and feedback on fluid I have sold the Amsoil MTG seems to be the closest to the OEM specs and gets great reviews.

Mercedes wants a GL-4 75w-90 fluid, which is what the MTG is.
 
When Standard Transmission and Gear rebuilt my transmission they recommended: Amsoil Synthetic Manual Synchromesh Transmission Fluid – 5W-30 (6 quarts + 1 quart over). Probably closer to the ATF+4 Mopar recommended.

I also experienced slow shifting in cold temps using Mobil Delvac 50. The Amsoil 5W-30 shifts fine.

I just installed a transmission gauge so will be monitoring temps. I ditched the Fast Coolers because they always leaked. I installed an oil cooler and will be checking it out this fall hunting season.
 
From my research and feedback on fluid I have sold the Amsoil MTG seems to be the closest to the OEM specs and gets great reviews.

Mercedes wants a GL-4 75w-90 fluid, which is what the MTG is.

Are you still selling AMSOIL MTG ..if so please PM me.
 
When Standard Transmission and Gear rebuilt my transmission they recommended: Amsoil Synthetic Manual Synchromesh Transmission Fluid – 5W-30 (6 quarts + 1 quart over). Probably closer to the ATF+4 Mopar recommended.

Probably more of a misunderstanding of fluid specs. Mercedes is pretty clear on a GL-4, of which Amsoil MTF is not but MTG is.

MTF 5w-30 is not on the same scale as 75w-90. In terms of gear lube viscosity it's like a 75w-80 (MTG is more like a 80w-90 than a 75w-90).

ATF +4 (Amsoil's) is similar to a straight 75w, which sounds similar but at 100°C it's significantly thinner than MTF and MTG.

Are you still selling AMSOIL MTG ..if so please PM me.

PM Sent
 
This is a pic of the G56 magnetic drain plug when I removed it with 50k miles on the Delvac 50.

Looking for informed opinions on the amount of metal ??

G56 drain plug.JPG
 
If I had a G56, I would try Torco RTF which has worked great in every other manual trans I have had. It never attacked synchros or degraded to black sludge like the Castrol Synthrq does in NV 4500s. It also gave lower HP drag than anything else I tested except the Castrol Syntorq.
 
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