So I have two 3800SC Fieros. An 88 and an 87. They both have Getrag 5-speeds. I know it is a weak transmission, but please read on to see the symptoms.

I'm fairly certain that the 88 has a broken shift fork as it has no 3rd or 4th gear. Ever.

The 87 seems to have a completely different issue. I'm trying to figure out if it is cable related or internal. Here is what it is doing:

--- If you keep it below 1500rpms, it shifts through all gears perfectly.
--- If you take it to around 2500rpms, when you go into 3rd there is nothing there. It's like neutral. However, if you move the gearshift from 2nd to 4th and then to 3rd, 3rd works fine.
--- If you take it over 3500-4000rpms, 3rd and 4th are both elike neutrals. If you slow back down and put it back in 2nd and lower the rpms, it goes back to shifting as above.

Just checking to see if it might be something that doesn't require pulling the trans.

Thanks!
Dave

You need to disconnect the cables at the transmission and move the levers by hand. You should feel each gear as you do this. If you still can't find the gears, then the trans needs to come out.

quote Originally posted by Gall757: You need to disconnect the cables at the transmission and move the levers by hand. You should feel each gear as you do this. If you still can't find the gears, then the trans needs to come out.

The gears all work perfectly when stopped or even driving slow and under 2000rpms. It only starts having issues as the rpms increase.

The synchros are not synchronizing? Fresh fluid maybe?

quote Originally posted by Gall757: The synchros are not synchronizing? Fresh fluid maybe?

It's really strange. No noises or granding or anything ever. The shifter moves into the position that it needs to smoothly and silently, just acts like a neutral. Raise the RPM's up to 3000+ and its neutral. Lower back down and shift back to 2nd and start over and shifts perfectly at lower rpms. Once in each gear, performs perfectly.

Contaminated Clutch? If you let it run that way for a bit do you smell anything?

quote Originally posted by Gall757: Contaminated Clutch? If you let it run that way for a bit do you smell anything?

Runs perfect. Pulls hard. No issues whatsoever except 3rd and 4th become complete neutral.