Reverse grinds only after trans is warm.

[richardc475]

My reverse grinds bad after driving for atleast 20 min, after the trans gets warm. In the first 20 min I can shift into reverse smooth as butter but after that its a no go, I have to play with it to get it into gear and it still grinds. Shifting from second and then into reverse only seems to help once in a while. Any Ideas?

Oh, Car is a 92 AWD Laser, fidanza 4.3 clutch.

 

[djtrickstick]

i would check tranny fluid, make sure its not too old and that you have enough, from there if all is good i would check clutch, my reverse always made a weird noise when i push into it but nothing was wrong, is it a grind or a like a pop sound?

 

[talondave]

My reverse grinds bad after driving for atleast 20 min, after the trans gets warm. In the first 20 min I can shift into reverse smooth as butter but after that its a no go, I have to play with it to get it into gear and it still grinds. Shifting from second and then into reverse only seems to help once in a while. Any Ideas?

Oh, Car is a 92 AWD Laser, fidanza 4.3 clutch.

Drain your transmission fluid, and replace it with, Redline MT90 (75-90).. That could help with your grinding problem, and its good stuff for your transmission!!

 

[richardc475]

i would check tranny fluid, make sure its not too old and that you have enough, from there if all is good i would check clutch, my reverse always made a weird noise when i push into it but nothing was wrong, is it a grind or a like a pop sound?

Trans fluid is good, its new. RP 75w90 gl4 compliant. I dont think its to do with the clutch as it only does this after I drive it for a while, before the fluid heats up it shifts smooth. It grinds really bad when the fluid is warm.

 

[djtrickstick]

hmm thats a pickle, cause why dont other gears gring, maybe a bad synchro? sorry bro im baffled

 

[richardc475]

hmm thats a pickle, cause why dont other gears gring, maybe a bad synchro? sorry bro im baffled

Reverse doesn't have a syncro.

 

[Lofty]

Both DSM trannies ive been through have a reverse grind, especially when you're rolling a little bit. Go into 4th and then reverse. It helps.

 

[richardc475]

I know all DSM;s grind, this is the 7th AWD one I have owned, I try all the little tricks, it just seems odd to only do it after the fluid gets warm.

 

[ChillinGST]

This sounds very similar to a problem I was having, only mine would scratch in first and reverse after warm up. I was able to adjust the clutch pedal linkage out just slightly and it cured my problem, shifts smoothy in all gears all day long. Just do a search for clutch pedal adjustment and you will find lots of info....

 

[Mindslayer]

Tranny fluid and adjust your CMC

 

[DSMopar]

Reverse doesn't have a syncro.

Yes it does, they just call it a 'brake' since it's 'synchronizing' with the trans side cover (which doesn't move).

 

[richardc475]

I am going to adjust the master rod today.

And BTW, there is no reverse syncro, thats why the input shaft has to come to a complete stop before you can engage reverse, if it is still spinning it will grind and not engage, or engage very rough. If you put your car in neutral running with the clutch out and then you go to put it straight into reverse chances are you wont go in without a grind as the input shaft has been spinning. You can then shift from second to reverse and use the second gear syncros to line everything up.

I posted as It seemed very odd that it only did it when warm. I will get that master adjustment done today and post the results.

Thanks for the replies.

 

[DSMopar]

I am going to adjust the master rod today.

And BTW, there is no reverse syncro, thats why the input shaft has to come to a complete stop before you can engage reverse, if it is still spinning it will grind and not engage, or engage very rough. If you put your car in neutral running with the clutch out and then you go to put it straight into reverse chances are you wont go in without a grind as the input shaft has been spinning. You can then shift from second to reverse and use the second gear syncros to line everything up.

I posted as It seemed very odd that it only did it when warm. I will get that master adjustment done today and post the results.

Thanks for the replies.

Apparently you don't read, there IS a synchro it's just called a 'brake' by the factory. Do you really think they designed it so you have to wait for the input shaft to spin down before you can put it in reverse?

 

[My1GLaser]

I'm interested in the outcome after you adjust the rod.

Mine doesn't really grind when warm, but def gets notchier in all gears after driving it for a few miles when the fluid warms up. Before that it shifts like butter and feels like a different tranny. I have a Dogbox racing Stage 3 tranny with about 2k miles on it. Everything else clutch/tranny related only has 500-1000 miles. I run 1qt Redline MTL, 1qt MT 90 & .75 qt of 50/50 lightweight & heavyweight shockproof mix.

I am getting the feeling that my fluid is too thin from the 1qt of MTL (70-80 IIRC). And I should try straight MT-90 instead of all this blended shit.

 

[richardc475]

Well, I went out and checked my fluid level, it was about 10ml over filled, after that fluid came out I have no problems whatsoever. I am still going to adjust the rod so it has a perfect adjustment, but with the fluid level at the correct spot i don't have an issue.

 

[My1GLaser]

Overfilled clutch fluid or tranny fluid?

 

[1fast97gsx]

Trans needs rebuilt, pretty simple ... if fluid is ok and didn't fix it you need to rebuild the trans. Chances are you have some chipped teeth and it's only becoming a factor when fluid is hot and parts expanded. Of course this is assuming your clutch is properly adjusted.

 

[richardc475]

Overfilled clutch fluid or tranny fluid?

Overfilled the trans. It hasn't ground once since the tiny amount drained out the fill hole.

 

[tscook3]

You might need to adjust your shifter alignment. There is a front to front and a side to side. You'd have to adjust the side to side maybe. But it could be the start of a tranny going bad. That is how mine started and a couple others did.