This was a very heated and debated topic which I'm will to bring back up and report. I'm at 68k miles on the fluid. I've ran for 2 or 3 winters now and have zero issues shifting. Fluid operated greatly in temperature to -35*F and zero issues. I just checked the fluid level and color and it still like it was poured in from the bucket. Clear amber color and discoloring yet. By early summer I'll have 100k miles on this fluid and will check again on the color I might push past the 100k mark if the color is still bright and clear. 

 

Now that I'm travelling 250 miles every Tuesday, Thursday, and Saturday hauling @MoparMom to Dialysis treatments in Ontario, OR I've had to drive in everything from subzero winter driving to scoring hot stuck in traffic. Eve3n toss in trailer hauling once in awhile when we decide to cheat and haul the RV down and camp out near the clinic so to cut down on the traveling. 

 

I can say without a doubt that Mobil 50 SAE transmission fluid is a SAFE fluid to use in an NV4500 transmission. It will not harm the syncros nor have any impact on the shift quality. I'll re-update this thread again when I cross the 100k mark. Currently I'm about to cross 329k miles on my next trip down. Figure 250 per day, 750 per week and 3,000 per month bare minimum mileage. This typically is higher because of other travels through out the days and weeks. Still I've not had a single issue with the transmission fluid or any poor shift qualities.

thanks for the info, i've not been able to source the mobile locally, i can get the Valvoline equivalent though. i've used Swepco's 711 on a few trans and it's always been great, on my current G56 with Amsoil MTG, i'm thinking about switching to something else soon. my manual says trans fluid ever 30K. seems excessive to me. but none the less. when i get 50K on it i'ma switch. 

might try this mobile stuff you speak of. 

After this bucket is gone I'm going to switch to Valvoline 50 SAE transmission fluid being cheaper in price and every NAPA store around me has it in stock. Valvoline is the same oil just their label. 

Good info ..... thanks Mike!

Just crossing 80k on the fluid. No issues to report. The fluid is now getting darker in color more of an engine oil brownish tint. Still no issues shifting gears. No syncro problems to report. Working great in winter cold down to -40*F to summer heat over 100*F. I've got just about 3 years on the transmission. 

 

I can with confidence say...

 

Mobil 50 SAE is safe for NV4500 use and will not cause any harm or shifting issues!

 

What does the cost per quart come out too? I realize your buying guide by the 5 gallon pail. I was told by my local dealer that they discontinued the Castrol Syntorq. This definitely gives people more options.  I just changed mine this spring, truck had 104k on it. Pretty sure it was original fluid, pretty dark when I drained it. I prefer and used Amsoil myself, it's stocked locally and was $14 a qt. Shifted 100% better afterward too. Glad to hear that mobile 50 is working for you.  

Works out to about 10 to 11 dollars a quart for what I bought and where. As for Valvoline I can do cheaper yet still 50 SAE GL-4 fluid.

Not a bad price. Always good to know there are different alternatives.  

Just checked local Napa has Valvoline 50 SAE for about 12 a quart. Price went up.

I know that this is an old thread, but I am hoping for some help. I have been to every parts house and farm supply store around, and I cannot find an SAE 50 in any brand. I suppose that I’ll be placing an order online. If anyone has a link to the proper fluid, I would greatly appreciate it. I want to make sure that I am getting the right stuff. 

 

how many quarts did you put in

4 quarts.

Will this work in the NV5600?

25 minutes ago, Marcus2000monster said:

Will this work in the NV5600?

No, synchromesh only, unless you want to try and repot back with results 

I've read of few people running something other than synchromesh but never heard the end results, probably sold the truck and never found out.

26 minutes ago, Marcus2000monster said:

Will this work in the NV5600?

What I've been told by my rebuilder "Yes." Now as for most here will say used PenzOil Synromesh oil. Basically PenzOil technically is a GL-4 fluid but it's too thin to make the rating.

On October 8, 2018 at 7:32 PM, Dieselfuture said:

No, synchromesh only, unless you want to try and repot back with results 

I've read of few people running something other than synchromesh but never heard the end results, probably sold the truck and never found out.

 

I've got just under 30,000 miles on my truck after I drained whatever was in there when I bought the truck and refilled with Redline MTL. Shifting performance improved substantially and has remained that way. Certainly not as comprehensive a test as Mike's, but it seems promising.

Exactly why the G56 transmission is filled with ATF+4. Even though Mercedes specs say GL-4 fluid should be used. Even the old Getrag 360 was just engine oil. Thinner viscosity oils always seem to shift better but how good is the protection in extreme heat?

On ‎10‎/‎8‎/‎2018 at 7:32 PM, Dieselfuture said:

No, synchromesh only, unless you want to try and repot back with results 

I've read of few people running something other than synchromesh but never heard the end results, probably sold the truck and never found out.

 

I use 15/40 diesel engine oil in all the trucks in my sig. I did buy a 5 gal bucket of Valvoline 50W synthetic manual transmission fluid a few years ago and tried it. The '91 and the Ford still has it and they both like it. The NV5600 in the '01 did not, so it has 15/40 again.