I just bought my friends 1993 Cadillac Seville. He sold it dirt cheap due to transmission problems. The 4.9 runs like a champ but the transmission "suddenly stopped going into gear". He says there were no previous problems (slipping etc.). I know the 93 trans is a common problem. I have heard of a trans fuse in the glove box but found nothing but the airbag panel. I checked the trans fluid in neutral (as per most cars) and noticed the level was surprisingly high. When shifting the rpm's fluctuate like it wants to go into gear but it doesn't. I'de rather not have to get a new transaxl but if that's what it takes that's what it takes. Any help on this issue would be greatly appreciated. I've always loved Cadillacs but this is my first. I'de like to be able to drive her at minimum cost. There's no reliable trans shops in my area and I don't want to trust my baby to some hack, nor pay the dealer price for a re-build.

 

if you are able to try to get codes to see what problems pop up. also what color is the fluid? Should be a redish pink color if recently changed. Also when you check the fluid level the transmission needs to be at normal operating temp if cold it may show higher than when warm. let us know what you come up with.

 

Check the trans fluid in PARK, idling and hot. The fuse you speak of will only cause the trans to not shift...it would NOT keep it from moving at all. I'm a little confused as to the actual problem...will the car not move at all, or will it move, but not shift? The #1 cause on the 4T80E trans that keeps it from moving is the pump shaft has sheared/twisted/broken. This would definitely explain why the trans fluid is high with the engine running. As a test to verify, Check the trans fluid BEFORE starting the engine(let it sit for at least 30 minutes first). Make a note of where the fluid is on the stick. Then start the engine, let it run for 30 seconds or so, then check the fluid again. If the fluid level does NOT change, the pump shaft is broken. That will require trans removal to repair. Sometimes, you get lucky, and it is simply a broken shaft. A lot of times, tho, the shaft is twisted due to a seized pump. IF the car moves, but will not shift, the most likely cause is the shift solenoids are broken. These are fairly easy to change, as they are located in the lower(bottom) transmission pan. Now I have confused myself...I thought you posted this was a 4.6(Northstar)....you actually said it is a 4.9. My bad....Two different engines, two different transmissions. However...the pump shaft and pump on the 4T60E trans also have the same problems as the 4T80E trans. It could also be the splines for the pump shaft in the torque converter have stripped.

 

Thanx for the help first off. I'm getting my local mechanic to pull the codes once I get payed (I work on cars that don't need a c.p.u.). The car won't go into gear at all. I was hoping it was the pump but it won't go forward or backward, plus I guess this trans doesn't use forward or backward pumps, also I hear there's no bands, so I'm lost. I'll post the codes when I get them, but it looks like a rebuild is necessary. I'm used to older vehicles, I can frame off a muscle car but computer cars get me. I noticed a sensor box where the linkage meets the trans. Could that be an issue? I want my caddy to drive but Ca. isn't conducive with minimal cost.

 

The "Sensor box" where the shift linkage connects to the trans is the Neutral Safety Switch, or MLP(Manual Lever Position) sensor, in electrical terms. The MLP will NOT cause a no movement issue.
The trans does have bands...3 of them, in fact. IF the low band is broken(common), it could cause a no-go.
Bottom line is, if the trans has fluid, and the torque converter is still bolted to the engine, any cause for a no-go is going to require trans removal to repair, with the exception of a broken/stripped pump shaft, or damaged pump. Those two things can be repaired in car by a qualified technician.
One other idea that might cause this is if the manual valve linkage for the valve body has become dis-connected. Never actually seen that happen, but it is a possibility. I HAVE forgotten to connect it a time or two, tho...