Synthetic ATF or Synthetic Synchromesh in T45 Trans?

P

paradigm

Member

Jul 18, 2007

50

0

6

Sep 23, 2011

#1

• Sep 23, 2011

• #1

I've been doing some searching on the forums, and cannot seem to find a conclusive answer as to what the best transmission fluid is for the T-45 trans (Specifically for the 99-00 GT cars).

The options I am considering are:
Amsoil ATF
Amsoil Synchromesh
GM Synchromesh

The Amsoil synchromesh is listed as an MTF, but the T-45 is supposed to use ATF? Can anyone provide a definitive answer?
Thanks

 

VTGT91

Member

Jan 4, 2007

58

0

7

Sep 23, 2011

#2

• Sep 23, 2011

• #2

The T45 transmission does require ATF. The clearences are so tight in some places that it cannot be properly oiled by thicker manual trans fluid or gear oil. I just did a complete rebuild of my T45 and used Mercon V as the fluid.

Sent from my DROIDX using Tapatalk

 

Night Shifter

Well-Known Member

Dec 24, 2005

1,710

27

59

Daytona

Sep 23, 2011

#3

• Sep 23, 2011

• #3

I ran penzoil synchomesh in my t45 with no issues whatsoever...shifted smith and ran fine....I use it in the t56 now

 

GDawg

Founding Member

Mar 22, 2002

1,469

19

68

Nevada

Sep 24, 2011

#4

• Sep 24, 2011

• #4

I run Royal Purple Synchromax.

 

bhuff30

Founding Member

Dec 11, 2001

6,037

35

129

Olathe KS

Sep 25, 2011

#5

• Sep 25, 2011

• #5

I went with Mobile 1 synthetic ATF in my T45. I bought it in the store, and have had good experience with mobile 1 oils. Probably cheaper than royal purple.

 

R

rconaway

Founding Member

Nov 11, 1999

1,415

3

39

Phoenix, Az.

Sep 29, 2011

#6

• Sep 29, 2011

• #6

please delete

 

jmc01gt

Member

Mar 11, 2010

60

4

9

Austin Texas

Oct 3, 2011

#7

• Oct 3, 2011

• #7

I used RP Synchromax, noticed less heat and smoother shifts on my T-45.

 

gt00

New Member

Aug 6, 2008

6

0

1

Oct 4, 2011

#8

• Oct 4, 2011

• #8

I use Mobil 1 and it works great, and costs a lot less than GM Synchromesh.

 

R

rconaway

Founding Member

Nov 11, 1999

1,415

3

39

Phoenix, Az.

Oct 24, 2011

#9

• Oct 24, 2011

• #9

I also used Mobil 1 and my T-45 is still running with 400-650rwhp at 80K miles. I doubt few cars have been abused this much on various tracks and WFO runs for 30 minutes. I've even had to replace the rear bearings as those have been worn out in this process. Tranny still works like a champ. My money is on Mobil 1.

On another note, I used Mobil 1 auto fluid in my Windstar. I've towed 6000lbs with that setup for 2000 mile stretches and the car went 180K with no problems. Another Windstar I have with less miles has written off 4th gear. This Windstar had standard tranny fluid and changes. I used Mobil 1 in several cars up to 250K miles with never a single problem.

 

mransr

Founding Member

Nov 3, 2000

1,188

36

98

Riverside, SoCal

Oct 24, 2011

#10

• Oct 24, 2011

• #10

I use Royal Purple Synchromesh and after nearly 1/4 of a million miles the trans is still working flawlessly (well, as flawlessly as a T-45 can)...

 

C

chunger

Founding Member

Dec 31, 2001

77

0

0

San Jose, CA

Nov 1, 2011

#11

• Nov 1, 2011

• #11

Wow, looks like I'm in the minority. I've run GM Synchromesh for a couple of years in mine.