Transmission grind

[DRAGUL]

Tried doing a search but revealed no answers. Took the car out tonight and had a issue where transmission started grinding on second and third. It is the Tremec 3650. It will go into gear fine with no grinding, but when the clutch is released is when it grinds. It is a quick loud grind, then it is fine with no noise or issues. Now I did have the rear tailshaft bushing replaced 3 months ago due to, the bushing being worn and causing the rear seal to leak. Along with the throwout and pilot bearing. They replaced the oil using Redline. I am wondering if the oil is causing synchro problems? I didn't have any problems before this, except the leak. Any help would be appreciated. Also car has the spec stage 3 clutch (previous owner) and stock cable setup.

 

[006]

Wrong fluid. Your synchros are FUBAR'ed.

http://www.svtperformance.com/forums/new-edge-cobras-51/616755-if-mercon-factory-fill-3650-a-2.html

Here is the fix:
http://www.stangnet.com/images/stories/docs/sn95_TSBs/04-15-06.pdf

p.s. The fix recommends Mercon/Dexron III which is the only fluid recomended for the TR3650 which in my opinion is a pile of dog shit transmission to begin with.

 

[RyanApfel]

Yep wrong fluid. Could be somthing else too but I'd start with the fluid.

 

[DRAGUL]

Thanks for the info. It seems there are so many posts on the internet of what to use and what not to use for this transmission. Some say use brand X while others say brand x will destroy the transmission. So what is the truth? Got confusing when I was trying to research this problem thinking it might be the oil used. Wonder if I put the correct fluid in will this solve the problem, or is the damage done.

 

[01yellercobra]

I ran Coastal brand Mercon in my 3650 and never had issues. So it doesn't need an expensive fluid. It's worth trying the fluid. You might be lucky and get away with a cheap fix.

 

[RyanApfel]

Thanks for the info. It seems there are so many posts on the internet of what to use and what not to use for this transmission. Some say use brand X while others say brand x will destroy the transmission. So what is the truth? Got confusing when I was trying to research this problem thinking it might be the oil used. Wonder if I put the correct fluid in will this solve the problem, or is the damage done.

6.Fill the transmission with 3.0 liters (6.3 pints) of Motorcraft Mercon ATF (XT-2-QDX)
I wouldn't put anything but motorcraft to be safe. I dout u did any permanent damage but anythings possible. Try new fluid and go from there

 

[Michaelslilgray]

It doesnt matter what kind you use as long as its mercon Dex III.... I use royal purple Dex III in mine and it works like a dream..

 

[DRAGUL]

Called Tremec today and spoke to two different people. Was told by both to use Mobil one synthetic atf as this is the best oil to use in the 3650. Was also told to disregard Ford's TSB and to make sure to fill it until it came out the side hole. But unfortunately was told the damage is probably already done by using the wrong oil.

 

[Snk-Byet01]

Called Tremec today and spoke to two different people. Was told by both to use Mobil one synthetic atf as this is the best oil to use in the 3650. Was also told to disregard Ford's TSB and to make sure to fill it until it came out the side hole. But unfortunately was told the damage is probably already done by using the wrong oil.

This is spoken from experience; Use Mercon ATF only, no synthetics. Also use only ~3.0 L. Do not fill up to the hole.

I was also confused and used Royal Purple synthetic up to the fill hole. At first things felt fine. Then I started getting a lock-out shifting between 2nd and 3rd. Things got worse in regards to shifting. I finally saw the light (3rd TSB from Tremac) and did what they suggested. I drained the RP (and no knock on RP products), flushed out the transmission with kerosine and after about a mile or two put ~3.0 L (no more) of Mercon ATF fluid back in (messy job). Not a problem since.

If you are living on the good side it's probable that your syncros might be okay. Just get the synthetic stuff out and don't overfill. From what I understand less fluid is better than too much.

Just my $.02.

- Mark