UOA MT 5sp. Volvo M47 II with Dexron @17000km

[miniac007]

Hi all,


This the UOA of a Volvo Manual 5 speeds M47 II transmission, mounted on 240/740/940.

This 1994 Gearbox has 332 000 km (~ 205 000 miles), and was quite worn when I get the car at 315 000 km (especially 2nd synchro)

Those gearbox need normally ATF type F but I have done a test with Dexron III during 17 000 km (~ 10 000 miles) to see if it can fit with synchromesh and friction modifier. Shifting was OK.

The result seems to be quite unusable as the Dexron seems to have washed all the old deposits in the tranny, and give now very high metal and insolubles...

Do you think anyway we can conclude the Dexron is no good for the synchro, or cooper/lead/tin are caused by old deposits like iron/aluminium ?

Q8 Auto 15 datasheet

 

[147_Grain]

Looks like you need a different oil with the high wear / metal count. Cutting the OCI in half to the 8-10K range and then resampling of a better oil, sinc TAN cross over TBN a while ago.

Doesn't your "Volvo Manual 5 speed M47 II transmission" take a 75W gear lube?

 

[miniac007]

Old volvo manual trans (M45/M46/M47) was using ATF Type F (volvo ref 1161 647) and in 1992, Volvo switched to synthetic MTF for M56/M90 new gearboxes (volvo ref 1161 745, 1161 645) and after to 1161 845 for powershift trans.

But now, Volvo has stopped selling ATF F.

Volvo now gives his 1161 745 and 1161 645 (75W) MTF as replacement for ATF F, but their viscosity profiles are totally different , especially at low temp.

I have tried an equivalent of 1161 645 (75W) with same viscosity curve on my tranny and shifting at low temps is awfull... Shifting with Dexron was OK.


Anyway, the problem seems to be the Dexron has washed all deposits. There is no reason to have 600 ppm of iron and 34 ppm aluminium in only 10 000 miles... With ATF F or Dexron or any oil...

I don't kwon where universal average comes from as Blackstone told me he hasn't any M47 average. Should be a mix of volvo trans.

But If I take as an example the Corvette MT filled with Dexron here: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2984359#Post2984359

I have a ratio iron/coper/tin/lead of 100/30/3/3 and if I adjust this ratio with iron at 600, x6, I have 600/180/18/18 which is exactly the ratio I have on the M47...

So it will be OK, but with 300 000 km washed deposits and not only 17 000 km metal wear...

Hard to conclude for me if the Dexron friction modifier worn the synchro or not...

 

[Pablo]

NEVER run Dexron in a M46/M47.

Find a light MTF. 10-11 cSt is what it needs, along with a different additive pack.

 

[SLCraig]

Originally Posted By: Pablo
NEVER run Dexron in a M46/M47.

Find a light MTF. 10-11 cSt is what it needs, along with a different additive pack.


A light MTF would be Amsoil MTF... 75w80 I believe

 

[trooper001]

Redline MTL (70w80) would also a good candidate w/a cSt of 10.6 - right in the middle, and it's virtually sheer proof. Bet it will fit the bill, much like the Amsoil ATF.

 

[badtlc]

And Redline MTL actually has GL-4 level protection.

 

[miniac007]

Ok, no Dexron...

I found that the BMW MTF-LT2 oils have the same viscosity curve and are synthetic. As I live in Sweden, I need to shift at -30°C (-22° F)

I have contacted Redline and here is their answer:

Pierre,

Thank you for contacting Red Line Oil, the MTL would be our recommendation for all around use, it would have a viscosity about 50% higher than a typical petroleum Type F at −30°C, the D4ATF about 40% lower viscosity. If low temperature shiftability is an issue the D4ATF would certainly be a good choice, wouldn’t cause any synchro problems.

Regards, Dave
Red Line Oil

The D4ATF is BMW MTF-LT2 and GL-4

I have also found the Ravenol MTF-2 also GL-4 and BMW MTF-LT2, and half price of D4ATF, and I posted a VOA here: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2987835


What do you think about those BMW MTF-LT2 to replace ATF F ?

Thanks

 

[badtlc]

Pentosin is the BMW fluid. So if you are contemplating the BMW, Pentosin MTF2 is the same thing. Maybe you can find it cheaper than the BMW labeled bottles.

If you are looking for other good options (low viscosity and GL-4 rated) here are some more you might be able to find cheaper:

- Fuchs FE 75W
- Castrol Syntrans FE 75W
- Elf TRJ (i think) 75W-80

There are a few others out there. Look for a 75W fluid that is GL-4 and you should be good.

 

[miniac007]

BMW MTF-LT2 match pretty well: