[sdlow619]

Hello Everyone ,

I have a 1995 Buick Roadmaster (123k) that I recently purchased with "no reverse". Since I bought it like this, I am not sure of the symptoms it had before the reverse went out. I tested 1st, 2nd, and Overdrive and they seem to work fine, no signs of slipping. The fluids are good and there are no leaks. I also checked the linkage to make sure it was engaging. The reverse would engage, but it does not drive in reverse.

I spent the past couple weeks researching all over the web and thought it could be that the Sunshell had broken. I then removed the transmission; I got a rebuild dvd to help me take it apart and get to the sunshell. I removed the sunshell and it looks good and not broken. Also I quickly inspected other hardware and everything seems to appear good. No bad wearing or anything broken. I also removed the oil pan and saw no metal shavings.

What else could it be? Low reverse clutches, oil pump, something in the valvebody, check ball or a bad solenoid?

I need help.....

[Crosley]

Originally Posted by sdlow619

Hello Everyone ,

I have a 1995 Buick Roadmaster (123k) that I recently purchased with "no reverse". Since I bought it like this, I am not sure of the symptoms it had before the reverse went out. I tested 1st, 2nd, and Overdrive and they seem to work fine, no signs of slipping. The fluids are good and there are no leaks. I also checked the linkage to make sure it was engaging. The reverse would engage, but it does not drive in reverse.

I spent the past couple weeks researching all over the web and thought it could be that the Sunshell had broken. I then removed the transmission; I got a rebuild dvd to help me take it apart and get to the sunshell. I removed the sunshell and it looks good and not broken. Also I quickly inspected other hardware and everything seems to appear good. No bad wearing or anything broken. I also removed the oil pan and saw no metal shavings.

What else could it be? Low reverse clutches, oil pump, something in the valvebody, check ball or a bad solenoid?

I need help.....

I hope you removed the trans pan first ... it has to come off to remove filter and solenoid from the pump to remove the pump from the trans case.

I do not see a mention of 3rd gear working correctly. You say

I tested 1st, 2nd, and Overdrive and they seem to work fine

Overdrive can not work without 3rd gear functioning correctly.

Solenoid has nothing to do with reverse.

If the trans operates in forward gears , then reverse would operate too.

Did you air check the reverse input drum?

Were the sealing rings OK on the stator for the reverse input drum?

Did you air check the low-reverse piston ( both sections) ?

post back when you can , let us know

[sdlow619]

Originally Posted by Crosley

I hope you removed the trans pan first ... it has to come off to remove filter and solenoid from the pump to remove the pump from the trans case.

Yes I removed the pan first, then the filter and the tcc solenoid. I then gently pryed the pump out with a screw driver. I used some info you had posted in a previous 4l60e thread.

Originally Posted by Crosley

I do not see a mention of 3rd gear working correctly. You say

Overdrive can not work without 3rd gear functioning correctly.

Solenoid has nothing to do with reverse.

If the trans operates in forward gears , then reverse would operate too.

Overdrive worked great, as did all the forward gears. When reverse would be engaged, It would just act like Park, No odd noises. In reverse you could step on the gas but it would not move.

I have also been looking in the GM 4L60e Manual, and reading about what is applied in Reverse and Park. It seems like the culprit might be the Reverse Input Clutch.

Originally Posted by Crosley

Did you air check the reverse input drum?

Were the sealing rings OK on the stator for the reverse input drum?

Did you air check the low-reverse piston ( both sections) ?

post back when you can , let us know

I have not air checked the reverse input drum or the low-reverse piston, I will do that soon. The sealing rings looked fine, but I will take another look.


Thanks for the help, I really appreciated it. I am new to all of this...

[Crosley]

I must apologize here;

I posted :

If the trans operates in forward gears , then reverse would operate too.

With that statement , I was referring to the trans pump operation... If the trans operates in forward gears , the pump would be functioning well enough for reverse to function too