Cutlass Transmission... No 1st or 4th gear

[CougarNut]

... Fixed

[slick]

External transmission modulator, mounted on the front of the tranny, real close to the underneath the airbox and the exhaust crossover. You will see a vacuum line going to it. Held in by one bolt(10mm I believe).

 

Though, I highly doubt it may be the modulator. How many miles are on the vehicle?

[Regal_GS_1989]

It shouldn't be the modulator, as that would only change the firmness of non WOT shifts, and not actually change the shift points. Does the speedometer work?

[CougarNut]

~110,000 miles or so I believe.

 

Yes, speedo works.

[Crazy K]

electronically controlled transmission.

 

I had this happen once on my 95. You are operating in failsafe mode because neither of the selonoids for you transmission are functioning. When it happened to me, I immediatrly located the plug on the top front of the transmission, and cleaned it. it was corroded and the loss of contact caused the selonoids to fail.

 

start there?

[slick]

electronically controlled transmission.

 

I had this happen once on my 95. You are operating in failsafe mode because neither of the selonoids for you transmission are functioning. When it happened to me, I immediatrly located the plug on the top front of the transmission, and cleaned it. it was corroded and the loss of contact caused the selonoids to fail.

 

start there?

 

IIRC, there still is a vacuum modulator. It isn't totally electronic.

[Crazy K]

electronically controlled transmission.

 

I had this happen once on my 95. You are operating in failsafe mode because neither of the selonoids for you transmission are functioning. When it happened to me, I immediatrly located the plug on the top front of the transmission, and cleaned it. it was corroded and the loss of contact caused the selonoids to fail.

 

start there?

 

IIRC, there still is a vacuum modulator. It isn't totally electronic.

correct, but I read that out of my service manual! let me find it again and I'll pst more.

[Crazy K]

in failsafe mode......

the car will in 3rd gear in D and OD

and will be in 2nd gear in 2 and 1st.

 

does it feel like this is the case?

[CougarNut]

Yeah basically. But OD is more like neutral Probably a completely separate problem.

[CougarNut]

Missed where you said to clean the plugs, but I tried that over the summer before trying to get 4th gear back. I made sure they were cleaned and put some electric goop in there.

[Regal_GS_1989]

The 4T60E has electronically controlled shift points only. The line pressure is still vacuum controlled, which is why they still have a vacuum modulator. With that, i'd say check the plug that Ken described, and if that checks out, then possibly take the car to a reputable transmission shop (ie Not AAMCO, or place like that) and have them check the car. They should be able to tell you whats wrong.

[Crazy K]

Yeah basically. But OD is more like neutral Probably a completely separate problem.

ok, could be both.

 

so when you have the car in o/d it acts like it is in neutral... it is not dropping our of fourth into third as I interpreted it, but into netrual instead?

 

P.S. we have a new vert section! (check it out!)

[CougarNut]

In O/D from a stop it's in 3rd. When it gets up to speed it slops into neutral.

[Crazy K]

what does you tranny fluid look like?

 

when was fluid last changed?

 

I would suspect that your trannys 4th clutch is worn out. I test drove a lumina with a 4t60-e, with a known weak 4th clutch and if you gave it too much throttle it would free rev. but.... does fourth seem good and strong cold? it may be weak pressure to the 4th clutch application stuff thingamajog. the line pressure should drop at the viscosity of the fluid decreases as the temp rises.

 

if you haven;t changed your fluid, you might try and see what happens... it may make it batter or worse, but a tranmissio shop would be good to consult with.

[CougarNut]

Trans fluid was replaced less then its service life ago. I did the change with the filter. I did post all this info in the top post.

 

Thanks for the help so far

 

I just wanted to see if this was a well known problem or common before getting reamed by a shop. I'd rather know what it is going in before having them work on it.

[joey b]

had the same prob with a 96 this summer. The wires from the PCM to the transmission somehow lost connectivity. Check there. Unfortunately I don't know which wires to probe on the PCM side.