I have an stock automatic tranny. It's a 85 GT 2.8L. In an automatic, what options are out there to drop the RPM's a bit. I seen the gas mileage notes, and was wondering about the options, and give and takes on this ? I had an iron duke 5 speed which could get up to 40 mpg, and my current 2.8 get's about 24-26 on the highway.

That mileage is normal for the stock Fiero 3 speed TH125c transmission. It was designed to operate best at 55mph back in the 80's. You can put in a 4 speed auto, or switch the car to a manual transmission, but that's a lot of work to save a few mpgs.

edit...you could expect about 32mpg highway from a 5 speed on the V6.

[This message has been edited by Gall757 (edited 02-03-2015).]

Tranny:


The old stock ones all get bad mileage.

[This message has been edited by randye (edited 02-03-2015).]

More like 28 with the 2.8/Getrag 5 speed, unless you're at a higher elevation like 1000 ft above sea level.

If you want more MPG and/or lower cruise RPM with the auto in the Fiero, you basically need to swap transmissions to get an overdrive, as the 3 speed doesn't have OD at all. Top gear is 1:1.

Depending on how many gears you want, and how much you want to spend, you can go up to a 6 speed automatic that has the metric bell pattern which bolts directly to the stock 2.8 engine. If you want to convert to manual, you can also choose between 4, 5, or 6 speed options, depending on how much you want to spend.

The cheapest/easiest swap to get you an overdrive gear, is the 440t4/4t60 (non-E version).

quote Originally posted by randye: Tranny: The old stock ones all get bad mileage.

But probably have plenty of gas!

Thanks, interesting.