Auto trans not shifting into 4th or O/D

Hey guys, my old man has a '91 GTO AWD non turbo automatic. A few years back the gearbox broke - a bracket for the trans band snapped off which was then welded back on. It then snapped again (due to the access only welded one side). This time took some more stuff off and welded it from both sides. After this it was fine. Car would shift 1-2-3-4 +OD on 3rd and 4th. However when he first bought the car it seemed to have another overdrive on 4th gear (almost like a 5th gear) which kicked in after a long drive on the motorway. Figured we'd take a look. Took the brain of the gearbox out along with the valves and stuff, gave it a clean and from one of the holes a small ball bearing and a spring came out. No idea what hole it came out from but I imagine it was some kind of pressure relief? Put the box back together again (minus ball and spring), car goes into PNDR12 fine but only goes into 1-2-3. Selecting overdrive on 3rd will cause the car to go into neutral. I imagine then that this ball and spring therefore helped build pressure in the gearbox for the box to shift the gears but also was a safety relief to allow oil to bypass through that port if the pressure was such that it could overcome the spring pressure? If anyone could help that'd be great, a trans diagram/pictures/guide would be great too, found a manual on the site but it was for a FWD trans.

Heres a few pics of the old girl, first time it's been moved in 3 or 4 years!

http://i217.photobucket.com/albums/c...pstfaaifzh.jpg

http://i217.photobucket.com/albums/c...ps09hvs6rd.jpg

http://i217.photobucket.com/albums/c...pslb5mb8dr.jpg

Cheers,

Ahmet

Quote:

---

Originally Posted by bodgemonkey

Hey guys, my old man has a '91 GTO AWD non turbo automatic. A few years back the gearbox broke - a bracket for the trans band snapped off which was then welded back on. It then snapped again (due to the access only welded one side). This time took some more stuff off and welded it from both sides. After this it was fine. Car would shift 1-2-3-4 +OD on 3rd and 4th. However when he first bought the car it seemed to have another overdrive on 4th gear (almost like a 5th gear) which kicked in after a long drive on the motorway. Figured we'd take a look. Took the brain of the gearbox out along with the valves and stuff, gave it a clean and from one of the holes a small ball bearing and a spring came out. No idea what hole it came out from but I imagine it was some kind of pressure relief? Put the box back together again (minus ball and spring), car goes into PNDR12 fine but only goes into 1-2-3. Selecting overdrive on 3rd will cause the car to go into neutral. I imagine then that this ball and spring therefore helped build pressure in the gearbox for the box to shift the gears but also was a safety relief to allow oil to bypass through that port if the pressure was such that it could overcome the spring pressure? If anyone could help that'd be great, a trans diagram/pictures/guide would be great too, found a manual on the site but it was for a FWD trans.

Heres a few pics of the old girl, first time it's been moved in 3 or 4 years!

http://i217.photobucket.com/albums/c...pstfaaifzh.jpg

http://i217.photobucket.com/albums/c...ps09hvs6rd.jpg

http://i217.photobucket.com/albums/c...pslb5mb8dr.jpg

Cheers,

Ahmet

---

What you have is a W4A33, most likely. Here's a link to an IPT video that shows the ball and spring you left out. It is actually a pressure relief valve and trans won't function right without it. The install location is near a plastic filter. There is also another steel ball that should be in nearby. All of this is shown from 7:00 to 7:20

Mitsubishi / DSM Shift Kit Installation Instuctions Part 4

There are also 4 other balls in the valve body. They are all on the other side of the main body from the one you left out. As long as you didn't take anything more than the lower valve body off, those 4 will be in place. If you have disturbed these other 4 steel balls, the Trans Lab kit instructions show where they all go. Manuals can be found in several internet places; they all pretty much are combo manuals with both the FWD and AWD trans. Just make sure you get one that has the W4A33. If all else fails, PM me and I'll e-mail you one. Hope this helps.

Absolutely brilliant, I'll have a look sometime this month and get it sorted. Thanks for the video.

Just need to fix up my mk1 golf before the GTO can have any TLC :tears_of_joy:

Good luck with the GTO when you get around to it. I just finished rebuilding one of these, including the Kiggly front clutch pack, IPT end clutch pack and Trans Lab 175 valve body upgrades. I still have the Trans Lab instructions which show all the ball locations, so if need be, I can take pics with my phone and send them to you. Just PM me with whatever you might need. By the way, that video is 4 of 4 on the Trans Lab kit install. The others are available on IPT's website.

Quote:

---

Originally Posted by bodgemonkey

Absolutely brilliant, I'll have a look sometime this month and get it sorted. Thanks for the video.

Just need to fix up my mk1 golf before the GTO can have any TLC :tears_of_joy:

---

Quote:

---

Originally Posted by BaadVR4

Good luck with the GTO when you get around to it. I just finished rebuilding one of these, including the Kiggly front clutch pack, IPT end clutch pack and Trans Lab 175 valve body upgrades. I still have the Trans Lab instructions which show all the ball locations, so if need be, I can take pics with my phone and send them to you. Just PM me with whatever you might need. By the way, that video is 4 of 4 on the Trans Lab kit install. The others are available on IPT's website.

---

Awesome, if you could take some pics then that would be great. It's stuck in the back of the garage for now though!
http://i217.photobucket.com/albums/c...ps96harjd9.jpg


Cheers,

Ahmet

Quote:

---

Originally Posted by bodgemonkey

Hey guys, my old man has a '91 GTO AWD non turbo automatic. A few years back the gearbox broke - a bracket for the trans band snapped off which was then welded back on. It then snapped again (due to the access only welded one side). This time took some more stuff off and welded it from both sides. After this it was fine. Car would shift 1-2-3-4 +OD on 3rd and 4th. However when he first bought the car it seemed to have another overdrive on 4th gear (almost like a 5th gear) which kicked in after a long drive on the motorway. Figured we'd take a look. Took the brain of the gearbox out along with the valves and stuff, gave it a clean and from one of the holes a small ball bearing and a spring came out. No idea what hole it came out from but I imagine it was some kind of pressure relief? Put the box back together again (minus ball and spring), car goes into PNDR12 fine but only goes into 1-2-3. Selecting overdrive on 3rd will cause the car to go into neutral. I imagine then that this ball and spring therefore helped build pressure in the gearbox for the box to shift the gears but also was a safety relief to allow oil to bypass through that port if the pressure was such that it could overcome the spring pressure? If anyone could help that'd be great, a trans diagram/pictures/guide would be great too, found a manual on the site but it was for a FWD trans.

Heres a few pics of the old girl, first time it's been moved in 3 or 4 years!

http://i217.photobucket.com/albums/c...pstfaaifzh.jpg

http://i217.photobucket.com/albums/c...ps09hvs6rd.jpg

http://i217.photobucket.com/albums/c...pslb5mb8dr.jpg

Cheers,

Ahmet

---

wow the awd automatic is a five speed I never knew that.

It's not a 5 speed. It's the same transmission as what comes in the auto awd DSMs (in a different case). Its a W4A33, ie 4 speed.

^ Yep. 3-speed + OD. Abysmally low gearing selection, but I guess I can't complain. The Vector W8 had the same number of gears (but no OD). :)

P.S.

Thanks, Milt, for all that you have done & all that you continue to do. :)