87 GN transmission

matt94z

New Member
Joined
Nov 22, 2009
I just bought my GN a few weeks ago. It has 102k miles on the car and I am now daily driving it. When I first started driving the car after it sat for almost 5 years, I noticed a few things that needed attention. I recently tuned it up and made a cold air intake, 3" custom DP back exhaust. It runs better now, bbut not perfect.

I also changed the trans fluid and filter, hoping to make the trans shift a little smoother. I noticed when I had the pan off that the inside was spotless and there was only a little bit of material on the magnet. The trans cant have more than 2k miles on it! At first I thought that the trans was beat, but now Im thinkin someone put a shift kit in it, that is not very DD friendly.

So the issues are... it shifts tooo FN hard! I have to let off from the 1st to 2nd shift if its wet because the thing will go sideways when it shifts!

Tell me if this is normal. It revvs out the 1st to 2nd shift to about 3500-4k RPM's at part throttle. and when it shifts it will snap your neck. It also revvs out 2nd to 3rd shift to about the same.

3rd gear: when cruising in 3rd gear, I noticed that its is almost like a stall until it reaches about 3k rpms then it engages. It does this until you hit about 51mph and it will shift into overdrive.

Down shifting is sluggish all the time and sometimes it scares me, cause it hits so hard! When coming to a stop, after being in OD, it feels like the converter stays locked and doesnt downshift until you are completely stopped.

The kickdown cable is properly adjusted. And the torque converter appears to be factory, its not painted or anything.

It shifts flawlessly while accelerating hard. Im not sure if this is just a characteristic of a certain shift kit or if this thing is messed up. It is consistant in all the things Ive mentioned, it hasnt gotten any better or worse in the last 1k miles.

If this is caused by a shift kit, is there an "un-shift kit" that I can get? I flippin hate it! Especially when it starts snowing soon, that will make it harder to drive.

Thanks!

-Matt
 
I would ask the previous owner what was done to the trans. Try loosening the T.V. cable a couple of clicks and see what happens.
 
The previous owner is long gone... I bought it from a buddy who didnt touch it for 5 years, he bought it from a guy in Ohio.So there goes that idea.

The cable was looser before, I adjusted it the proper way and it still shifts the same as far as I can tell.
 
Replace the lockup solenoid. Its under the pan and held in by 2 small bolts. Any aftermarket solenoid will work. If you use a universal one for a 200/700 you will need to use the 2 spacer washers included with the solenoid.
 
Matt it apperars that you have an issue with the tv limit valve or tv valve causing excessive oil pressure to enter the tv upshift oil circuit causing late shifts and higher pressure at the line bias valve resulting in firm shifts at short throttle angles.This problem SHOULD be easy to fix.First thing I recommend you do is take off slow and note 1/2 shift rpm.Then disconnect the cable and take off slow and with the same throttle pressure and note shift rpm.Reconnect cable and post the results and we can go further.
 
Replace the lockup solenoid. Its under the pan and held in by 2 small bolts. Any aftermarket solenoid will work. If you use a universal one for a 200/700 you will need to use the 2 spacer washers included with the solenoid.

Can I just unplug the solenoid to see if that is causing my problems?
 
Ok I fixed the issues with my trans.

1.) At some point the previous owner swapped over to vac brakes and the Branke Pedal L/U switch was out of adjustment. It was pushed all the way forward, so the only time the trans would come out of L/U is either when the brakes were stabbed hard or at about 1mph.

2.) the TV cable was too tight. I adjusted it several times, using the ratchet adjustment, but it wasnt going out far enough. Im guessing the cable is old and stretched and needs replaced. I loosened it by 2 clicks and the trans shifts perfect, doesnt ride out any gears and doesnt do that wierd neutral thing before shifting. Down shifts are now predictable and smooth at about 1/2 to 3/4 throttle. It still shifts nice and firm, but MUCH more streetable now!

Thanks for everyones help!
 
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