My 1992 Cutlass Supreme 3.1 shifts out of first at "orange-line" (5500) at 40 MPH. It used to shift at about 44 or 45. Is that a result of transmission slipping, or some other part not giving 100%? It doesn't bog, or have any idling or other problems.

Hi Dankraft, hello everyone,

Welcome to TOC.


No.


Could be one (or more) of many things, internal or extrnal.

How long (time/miles) since the change started?

Regards, Norm

About 7-8 months. I had the engine replaced in December 2005. 1-2 shift occurred, as expected, at 45 MPH and 5500 RPM, for about 2 months. Tach redline is at 6,000, but it has an orange zone from 5,500 to 6,000. Normally shifts at 5,500. As I recall, it shifted one time out of first at 6,000 RPM, though still not even at 45 MPH. The "problem" seems to have started shortly after that. Engine was replaced at 105,000 miles, 6,000 RPM shift happened at 108,000 or so, and all but engine have 115,000 now.
I put "problem" in quotation marks because it's not a vital issue for the moment, as I don't "street race" my sedan. I just started noticing it when pulling out into not-so-sparse traffic, and wanting to get to the 50MPH limit before the next wave arrived.
Fuel economy does not appear to be reduced, and there's no lack of thrust compared to before.
Transmission slip is a term I've heard, although I'm not sure of the meaning. Hope mentioning it wasn't too uninformed.
Thanks for your time. By the way, just out of curiousity, how many miles do you have on your 437?

Anytime the trans allows the engine to rev higher, or lower, than it should, in gear or during a shift, it's called slipping. It's the same as "slipping" a manual clutch.

Shift points used to vary from shift to shift in the older stuff. I can't go any farther than I have with your E trans.


Since it "grew" from 431 to 437? I would guess, between 3 and 4 miles. Engine is fully streetable, trans and rear end are not, yet.


Red Coupe with the 431.

Engine had about 14K street/highway miles, and just over 420 passes when I pulled it out of my Grey Coupe and put it in this one. Later, it lost a rod bearing, and I was forced to "massage" it to 437".

Norm

So my 1992 has the electronic transmission? I always wondered about that. As far as I could tell, it was introduced at different times for different cars. Buicks had it as early as 1992, maybe earlier, and the Chevy Lumina got all the good stuff ("new" 3100 engine, 4T60-E) in 1994 (maybe 1995?), so I was never sure. I've seen Cutlasses after the 1994 redesign, and their shift indicator read P R N D 3 2 1, while mine reads P R N OD D 2 1, as does a friend's 1988 Regal. I never would have gotten around to checking myself, decoding the VIN, or anything like that.

By the way, nice car. Do you happen to know when red became a widely available color? Maybe a stupid question, but I'm 21, and that car was built before even my parents were born.

Thanks for the compliment.

IIRC, it was an '80s VW color. I bought it because the PO needed cash, and the price was more than right.


My guess would be in the twenties, on anything except Fords.

Norm

I may be mistaken, but I believe my 91 lumina has the electronic transmission. It has the old 3.1, but I am fairly certian that it has the 4T60-E.

Andrew

No, I got the years crossed. Glad I caught it before anyone else did. I've got an image to maintain.

Norm

I looked it up too. My car doesnt have that transmission in it.

Sorry for the hijack

Andrew

Thanks, all.
Andrew, what sort of city mileage do you get? I used to get a fairly consistent 21.5 city, and 29.5 highway once, but I now get almost always 17.8-17.9 city. I wonder if I have an exhaust problem, as I have new plugs, Mobil-1 5W-30 (maybe doesn't do all that much, but I want to cover all my bases), used that STP FI cleaner, and I go pretty easy on it. The exhaust sounds like an older, bigger-engined car lately. It may be cool-sounding to some, but I can just hear the gas being wasted.

I passed a beautifully restored Bel-Air the other day, and his exhaust sound reminded me of my own. My car's sound merits a good 50 more cubes.


Daniel

I get about the same milage. I usually get mid 30s on the highway though. One thing that happened to me, that is pretty common for the 3.1 was a vaccum leak. The source of it was the plastic vac. lines that go from the throttle body to the intake, underneath the plenum. Car had no power, got poor milage, shifted funny, but it didnt sound like a vac leak to me. Apparantly these lines are somewhat known for getting brittle and breaking or cracking.

If you replace them, be careful with the plenum bolts, they break easily.

I am thinking, since the engine was replaced 10,000 miles ago, that it is probably something simple, such as a vac leak that has developed.

What do you mean by your statement about the exhaust? You mean loud? Or Rattling? If its loud, it wont necessarily waste gas, unless its plugged.

Andrew

It doesn't rattle, but just sounds like an older V8 car idling, with the volume "turned down," so to speak. My father is of the opinion that the car is "just getting old." I tend to agree, but I still wonder. As far as being plugged, it sounds like it is everything but. No matter. For a 15-year-old car rated for 19 city (automatic), I suppose just under 18 isn't bad. Definitely makes me feel a little better that somebody else with the same car (Lumina) gets the same city mileage.

Off topic, but of interest to me as a brash, young Olds driver: The magazine acceleration times for this generation 3.1 W-body are all around 9.8 or 10 seconds to 60 MPH. I don't doubt the professional testers' ability to measure performance, but that time is more than a little on the "safe" side. I have calculated the time to be about 8 seconds, but would value any input on the matter. I see a 1994 Cutlass owner posted a 16-second quarter-mile time, which would correspond with an 8-second 0-60.

Not that I mean to test it, but I must wonder, after having recently driven a 1995 BMW 325is (auto), rated 8.5 seconds to 60, yet it was most definitely not as powerful as the Cutlass. Maybe a better car, but not in a straight line.

Though the 325 is rated 181 lb-ft, and has shorter gearing, thus more effective torque, it didn't have the same thrust. I often wonder about different companies' ratings. Either GM is conservative, or most others are very optimistic.

If it's even worth mentioning, what do you all think?

My 3.8 sounds the same, even likes to go "pop, pop, pop" if you rev it and let off quickly. Although I have a gutted cat, so that might be why.

Nothing sounds like a V8, except, another V8.


Do not get too involved in those numbers. They only tell a small part of the story. Doesn't your 2 second discrepancy, tell you anything?


With an 8 second, 60 ft time? There is another car with a 15.61@116. I would guess his 60' to be about 3 seconds.


It might. On the other hand, it might not have any relationship, at all.

Norm

"Nothing sounds like a V8, except, another V8."

I didn't mean to step on hallowed ground there. I didn't say it performed like a V8, just had the same tonal quality. It doesn't have the V8 rumble shaking windows and all, but the sound is there. I must have come across like someone who puts a fart cannon on a Civic and says it sounds like a bigger motor, so must have more power.

Again, my statement about the sound was not an attempt at childish bragging. No offense was meant to the V8 gods.