Just making sure that my transmission is OK. My 4 cyl./3 speed is doing about 3000rpm at 60 and about 4500 at 80. Does that sound right to you guys?

Thanks.

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What is normal anyway?

I have an '86 2m4, auto, that runs about 3000 at 65mph.

Depending on year of car, the autos had different final drive ratios that would account for some of the difference in highway RPM, but yours seems too high for this to be the reason.

Are you sure your torque converter is locking? Slippage in the trans could account for the high RPM's.

Mine sits at 3200 rpm at 70mph and 85mph it sits at 3900rpm and at 100mph it sits at about 4500rpm. I bet the torque converter lock-up solenoid isn't working on yours. It won't affect performance (0-60) but will affect gas mileage/economy.

Actually, I can't quite tell when the car is shifting into third. It gives a subtle clunk, but not what it does in second. I've been wondering if their were torq converter problems. What would be a possible fix?

Shifting into 3rd ( or 3rd and 4th in a four speed ) is always more subtle so don't worry about it.
Test the lock up by driving at a steady 55 or so and watch the tach. The TCC is supposed to disengage when you step on the brake so just lightly step on the brake. Not enough to engage the brake just light the brake lights. RPM's should jump just a little, one or two hundred RPM, if the lockup is working properly.

So, basically you're saying take it to a transmission shop?

No I'm saying it sounds fine to me. You don't report slipping gears or harsh engagement. Only issue is the TCC which you can check later today and they almost never fail by not engaging. They fail by not releasing.

unless the previous owner had it not releasing and it is unplugged??

Good one PBJ. OK so if the previous owner disconnected it you will not see the RPM rise when you drive it. Here's a couple of links on the TCC: http://www.kichline.com/chuck/fiero/TCC.htm http://www.franken.de/users/dagobah/luke/tcc.html

Well, I've only had this problem since rebuilding the engine. My worry is that not only are the rpms high on the highway, but the car seems to hum obnoxiously after 55-60mph. My only other thought on that would be the engine (cradle) mounts.

See if the hum goes away when you test the TCC. Gotta run, wife calling.

Thanks for the TCC link. Will check that out when I get a chance. I'm sure that the plug is in, but maybe it has a bad connection. The car doesn't stall at all though.

quote Originally posted by normalicy: Just making sure that my transmission is OK. My 4 cyl./3 speed is doing about 3000rpm at 60 and about 4500 at 80. Does that sound right to you guys? Thanks.

I have an 84 auto and my rpm's are about the same as yours, though i dont take it to 85 for fear of blowing it up (done it before). Though I know my TCC is broken, and i have disconnected it...

Yup those RPM / Speed ranges sound about right. the TCC will only lower the RPM about 3 or 4 thou above 40 or so.

Ive had my fiero at about 4600 rpm in 3rd gear and my 85mph speedo was back around 5mph or so. At 70 im turning about 3000rpm. This is with an 88 coupe auto.

Dont forget, tire size, (actual height of tire) will effectivly change you final ratio. I put pretty tall tires on mine and I run around 3,000 at 70 too. Low profile tires can lower the ratio quite a bit, make it quicker out of the hole, but loose a lot of top end.

Thanks all. Maybe I just tightened the engine mounts too much. Does anyone know when too much is too much?

84Bill, hope you didn't do that just for me.

I have factory wheels on mine and it runs about 25\26 hundred rpm at 60 but they say their are diffrent trany's so i suppose this dosent help much. But before its warms up it does run about 3000 at 60 but is that normal?

quote Originally posted by normalicy: Thanks all. Maybe I just tightened the engine mounts too much. Does anyone know when too much is too much? 84Bill, hope you didn't do that just for me.

Hehe nah did that going to carlisle. and trust me I only did that long enough to take the picture