Syncromax Tranny oil after 7k miles

Today I swapped out the Syncromax transmission oil after just 7k miles. It was grayish and from the looks of it has degraded badly. I replaced it with OEM LT2 oil and the car shifted better than it had the last 2k miles.

For those of you thinking of going with Syncromax. I'd recommend sticking with OEM.

I change mine every year as part of the fall service, but I can tell you the synchromax definitely makes the S6S-420G shift better than the OEM fill.

Are we supposed to be using Syncromax or Gear Oil?

Royal Purple's site says Syncromax is automatic transmisssions, and manual transmission that call for automatic transmission fluids. Another product named Gear Oil is for manual transmissions.

Originally Posted by wildag

are we supposed to be using syncromax or gear oil?

Royal purple's site says syncromax is automatic transmisssions, and manual transmission that call for automatic transmission fluids. Another product named gear oil is for manual transmissions.

atf

When I changed the OEM transmission fluid at 60k, it also looked grayish.

I put Pentosin MTF2 back in since my research indicated that it was the actual OEM fluid. It's for use in Getrag and ZF manual transmissions.

So far so good - no problems.

It's pretty well reported that synchromax is crap.

Originally Posted by blau335

It's pretty well reported that synchromax is crap.

I've seen lots of reports on RP in the M diff is crap,
but haven't seen the same about synchromax in the tranny

What do you use?

Personally, I think synchromax is great, and I have tried everything.

The other option is the Redline Cocktail, or whatever BMW is using currently. However, BMW thinks its lifetime fill, so I think they expect it to last for 50,001 miles.

Mobil 1 runs the coolest in the diff, so I assume its the best.

The CRX used 10w30 motor oil in the tranny, but that thing was bullet proof.

Ran it for months with no fluid in it, and it didn't shift all that well. However, refilled it and it ran like a champ till it sold.

Originally Posted by Mpire

Personally, I think synchromax is great, and I have tried everything.

......

I'm the same.
I change it often though.

I doubt I get 5k even when I let it go 2 years.

I think after a couple years it has probably absorbed too much moisture.

Originally Posted by blau335

It's pretty well reported that synchromax is crap.

I would like to see those reports - The RP Diff fluid has been beat up; as has the Red Line. My surf through the Internet has not yielded "crap" on the ATF?

The guys over at Blackstone labs seem to think my Synchromax is good as new when I change it.

Originally Posted by blau335

It's pretty well reported that synchromax is crap.

My experience with Synchromax has been very positive. I had experienced a 3>4 notchy shift, and the dealer couldn't fix it. They had tried a tranny flush with new OEM fluid with no improvement.

They finally put in RP Sychromax (which I supplied) and the problem went away almost completely. The one thing that keeps me from attributing this all to the Synchromax is that the dealer also replace the OEM tranny mounts with Rogue Engineering ones at the same time as the new fluid.

In any case, for the ~ 3,000 miles since these changes the tranny has been a joy.

EB

Synchromax has always improved the shift action in my BMWs, and I was a huge skeptic when I first heard about it. Tried it in the 335 and was so pleased with the improvement that I started using it in the Z4M and MCS. When I was researching it I saw a lot of positive reviews and favorable analysis results. At the same time I switched to RP in the 335 trans we switched my friend's 335 trans over to Redline and it was not any better feeling than OE and worse feeling than OE within a few thousand miles. Not enough miles on my cars yet for analysis but probably this year it will be time to change it out and send it in to Blackstone.

I plan to stick with OE fluid in the rear diff though.......