[evanjp]

so after reading countless threads on tranny fluid, i still am having a hard time deciding to go with pennzoil syncromesh or GM syncromesh (which i believe are "manual transmission" fluids) as opposed to the factory recommended mercon V (i believe which is an "automatic transmission" fluid. so what's the dealio? what should i do here? i'm having a small crunch shifting from 1-2 and 2-3, which i believe might be associated with my clutch issue of either a beginning-to-fail clutch, or another stretched clutch cable (yippie), but it might also have to do with not changing my tranny fluid yet (50,000 miles as of a couple days ago)

so... can someone give me the absolute best stuff for my transmission? it's the tr3650, 2002 mustang gt. i do some drag racing, only have a couple bolt ons, but plan on maybe a couple more bolt ons (lol) with a tuner and at one point next year a dyno tune....

[mrbigjeep]

syncromesh. end of story.

tremec recommends it.

[jonnyspeed]

What brand?

[Bajis]

Tremec told me Mobil 1 ATF, I asked about GM Synchromesh.. they said its just as fine, I put in the gm synchromesh. My 5th gear sounds like shit, lots of crunching going on when in gear...But shifting is much smoother.

[1_nice_03_gt]

what part # is it for the gm synchromesh cu i dont want to go in n ask for synchromesh for a mustang lol

[IrishGT]

Originally Posted by Bajis Tremec told me Mobil 1 ATF, I asked about GM Synchromesh.. they said its just as fine, I put in the gm synchromesh. My 5th gear sounds like shit, lots of crunching going on when in gear...But shifting is much smoother.

i'm beginning to wonder if thats a normal thing for 5th gear.. i have the aluminum shift knob and any little grind noise is like amplified cuz its metal... but yea 5th grinds constantly and sometimes i get a grind in neutral when moving... it a noisey trans

[Bajis]

Originally Posted by IrishGT i'm beginning to wonder if thats a normal thing for 5th gear.. i have the aluminum shift knob and any little grind noise is like amplified cuz its metal... but yea 5th grinds constantly and sometimes i get a grind in neutral when moving... it a noisey trans

Yeah everyone Ive talked to says its normal, same when rolling at like 70 mph in neutral I still can somewhat hear it.. If the tranny goes on me I guess it just means its t56 time!

[Stang187]

If I use GM tranny fluid instead of Mercon V would I still have to change the fluid every 30k miles or would it be extended to 100k?

[Everett]

Look man amsoil synchromesh is the best fluid money can buy. It's expensive but you can go twice as far between fluid changes. Go to amsoil.com and read up on it yourself. Or google it. Trust me you get what you pay for

[brharris777]

Originally Posted by Everett Look man amsoil synchromesh is the best fluid money can buy. It's expensive but you can go twice as far between fluid changes. Go to amsoil.com and read up on it yourself. Or google it. Trust me you get what you pay for

+1 i have posted a few times pushing the Amsoil synchromesh because i did the swap from ATF to synchromesh when i did my clutch and i couldnt be happier with it. gear shift smoother, reverse isnt as finiky as it used to be, but i will say that at speed that shift to 5th is still sketchy as hell. And since Amsoil is a sponsor of mine i suppose i am obligated to tell you that it is honestly the best fluid you can run and honestly i think it is. It says its a 5w-30 but thats just the viscosity of it, its the additive package that makes it what it is.

[blownstang]

Whats this 5th gear, neutral, reverse grinding stuff? Never had a problem with any of those. Second gear only crunches when its cold. 35,000 mi on the stock fluid and the last 17,000 on Royal Purple Synchromax.

[brharris777]

my reverse doesnt always like to engage in my car and the only way to engage it is to bump the synchroes in a forward gear then go back to reverse and it slips in. My 5th gear feels a bit funky when shifting at high RPM form 4th to 5th

[slo3gt]

Personally, I'm going with royal purple in mine. Haven't decided on motor oil though,thinking Dyson syn or Schaeffers.

[zak2006]

[jonwrong]

GM Sychromesh helped my third gear engagement. I have heard good things about Redline D4. Those are the only good choices IMO.

[blkfordsedan]

I have talked to 3 different engineers from Tremec on 3 different occasions. In each case, I was told not to use Syncromesh, Royal Purple or Amzoil synthetic fluid. The reason, according to them, was because of the carbon fiber material used on the synchros in the 3650. Supposedly, the above synthetics will attack the bonding adhesive and will result in failure. They did state that the factory fill was Mobil 1 ATF, but the base used in Mobil 1 would not effect the adhesive. This may just be their way of covering their ass because Ford filled it with Mobil 1, who knows. Regardless, they recommend using either Mobil 1 ATF or regular Mercon ATF. I do know that Synchromesh is designed for transmissions with brass synchros and materials that are compatable with it.

I'm not trying to "dis" anyone using these fluids. They are all excellent lubes and there are plenty of people using them without issue. I'm just offering up what I have been told by Tremec, so take it for what it's worth. Personally, I have been very lucky with the 3650 in my '04. I have 60K miles and it shifts perfect with no grinding in any gear, even at temps below 10F.

[jonnyspeed]

never gonna get a straight answer in this thread haha