Redline MTL vs. Stock ATF+4 in Dodge SRT-4 FWD Transaxle

[Idrinkmotoroil]

I've been curious about the ability of thin ATF fluids protecting high hp fwd transmissions containing differentials all in one housing. I think I've gotten my answer by these two reports, particulary considering the mileage differences. All opinions welcomed. First sample is Redline MTL used 25,000 kms , including some road racing and 1/4 racing, hard driving conditions. Second sample is stock Chrysler ATF+4 with 4 oz of Mopar friction modifier, it was used about half the distance at 10,000 kms, no road racing, but a few 1/4 mile runs. here are the numbers:

Iron - 24 , 81
Aluminum - 5 , 16
Chrome - 0 , 1
Copper - 33 , 22
Lead - 15 , 25
Silicon- 20, 28
Zinc - 2184, 50
Visc cst.- 9.6 , 5.9

I was hoping the copper numbers on the Redline MTL would have been better, but I guess for over double the miles it is still better than the stock atf+4 fluid. Look how little zinc is in the stock fluid compared to Redline MTL, and viscosity is quite low too - very thin.

I've been swapping fluids trying to improve the shifting of this tranny as it hasn't been great. Still lots of copper coming off the snychros I think , with either fluid ?. I'm using Amsoil MTF right now and hope to have a comparison later down the road. I never liked the idea of using a thin ATF fluid in a manual tranny, I think this report confirms my suspicions. thin viscosity, low anti-wear additives, doesn't bode well in high hp applications.

I have particle count info for the atf+4 but I never got any on the Redline MTL sample so not able to compare that info. I can post it if anyone wants to see it though.
love to hear some opinions.

Joey

 

[TurboLuver]

Joey, I wonder why the Aluminum 3x higher with the ATF+4? Could the ATF be reacting with the Aluminum housing or something?

 

[Idrinkmotoroil]

I'm not sure what the aluminum would be from in the tranny, perhaps bearing material, which would make sense on a thinner fluid such as ATF+4, and almost no anti-wear protection (very low zinc). Our engines use almuminum bearings, perhaps the tranny has some as well as lead bearings. I guess it could also be material from the production process, ATF has some powerful cleaning abilities if nothing else.

 

[unDummy]

Some of the aluminum is from the tranny case. There will always be casting/MFG/machining junk in a new transmission. Some of the drop in PPM's is simply from the "washing" of the tranny when the fluid is changed, and is why I recommend a very early change on ALL OEM fluids.

 

[Steve S]

In most all fwd trans the ring gear is not a hypoid ring gear ,so a ep type lube is not needed.

 

[bulwnkl]

So, how much of the lower wear with the Redline is due to its higher viscosity and how much is due to its better chemistry? Have you ever had Redline's C+ in it? That would be a very nice, direct comparison if you have.

 

[Steve S]

late thought, Was the stock atf the original fill? .If it was the oil should show highernumbers.