My friend has a 1998 Mustang with a V-6 and a 5-speed manual transmission [T5OD 5 SPD......MA]. It shifts very sloppily and causes mis-shift under hard accelerating. This transmission calls for an ATF. The car has 190k miles on it. So we switched out the stock fluid and added in AMSOIL's ATF. He reports back no improvement and says it's in some cases worse now.
I've been doing some reading. In the Royal Purple brochure it lists a Syncromax fluid that is for manual transmissions that call for ATF. So I'm thinking this may be a better fluid. As a side note, Royal Purple claims this is a GL-4 & GL-5 fluid, which gives me thoughts of trying it in my 2009 Mazdaspeed 3. Since it's a GL-4 transmission (6 speed, I think Getrag makes it). Would this fluid work for me as well?
After more research, it seems GM and Pennzoil both make a Synchromesh fluid that is liked by many. Would this be compatible also?
Now I'm reading about this "BG Syncro Shift II" and it has a lot of fans.
Then I look at AMSOIL and see thy have a synchromesh as well.
Anyhow, any advice would be greatly appreciated. We are trying desperately to improve the shifting on this project car of his as this is his and my new "garage queen" that we are working on restoring and making into a sleeper. Just for fun.
P.S. For my 09 MS3 I bought some billet aluminum shifter bushings. This made a very nice difference in the feel of the shifter gates and helped in a big way becoming stuck between gears (in the cusshy part) on super-hard speed shifts. Do they make such a thing for his 99 Mustang? If so, where can we buy them? Thanks!
I've been doing some reading. In the Royal Purple brochure it lists a Syncromax fluid that is for manual transmissions that call for ATF. So I'm thinking this may be a better fluid. As a side note, Royal Purple claims this is a GL-4 & GL-5 fluid, which gives me thoughts of trying it in my 2009 Mazdaspeed 3. Since it's a GL-4 transmission (6 speed, I think Getrag makes it). Would this fluid work for me as well?
After more research, it seems GM and Pennzoil both make a Synchromesh fluid that is liked by many. Would this be compatible also?
Now I'm reading about this "BG Syncro Shift II" and it has a lot of fans.
Then I look at AMSOIL and see thy have a synchromesh as well.
Anyhow, any advice would be greatly appreciated. We are trying desperately to improve the shifting on this project car of his as this is his and my new "garage queen" that we are working on restoring and making into a sleeper. Just for fun.
P.S. For my 09 MS3 I bought some billet aluminum shifter bushings. This made a very nice difference in the feel of the shifter gates and helped in a big way becoming stuck between gears (in the cusshy part) on super-hard speed shifts. Do they make such a thing for his 99 Mustang? If so, where can we buy them? Thanks!
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