 
     |
| Automatic Transmissions for Fiero GTs (Page 1/2) |
|
belldan
|
FEB 26, 02:03 PM
|
|
|
Hello Everyone! I'm in the market for a Fiero GT and would like to know if the V-6 engines and automatic transmissions are reliable. I really appreciate any and all information. Also, I read that parts for the 1988 model may be hard to find so kindly advise if what I read is or is not true. Again, thanks very much for taking the time to respond ! ------------------
Danny Bell
|
|
|
Patrick
|
FEB 26, 04:13 PM
|
|
| quote | Originally posted by belldan:
...would like to know if the V-6 engines and automatic transmissions are reliable.
|
|
Depends on your definition of "reliable". If all you want to do is to to put gas in the tank and drive... then buying an almost 40 year old car probably wouldn't be the wisest choice. It also greatly depends on the maintenance history of the individual vehicle.
Unless you're mechanically proficient yourself, or have deep pockets to be paying someone else to be doing the mechanical upkeep, you might regret buying a four decades old car.
|
|
|
|
theogre
|
FEB 26, 04:31 PM
|
|
Fiero only has TH125c for Auto Trans w/ different "final" gearing for model and trim level and fairly reliable if don't beat the hell out of them.
Some Fiero have been swap to have 4T60 auto w/ Over Drive and ok too.
One issue is a solenoid valve to control Torque Convert Locking...
Many unplug this because "old type" valve "breaks" and TC stays lock.
In 4T60 and other, many ignore this wiring and never locks the TC.
No Lock hurts MPG and heats the auto trans more.
88 Fiero "big problem" is can't get brake and suspension parts. Was hard to get these parts 15-20 years ago and unobtainium now in most places.------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave
|
|
|
|
sanderson231
|
FEB 26, 08:43 PM
|
|
|
Fieros are way more fun with a manual transmission and I have both manual and automaitics ------------------
formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged
|
|
|
Patrick
|
FEB 26, 09:22 PM
|
|
| quote | Originally posted by sanderson231:
Fieros are way more fun with a manual transmission...
|
|
Absolutely! Plus there is just so much to go wrong with an automatic. With a manual... maybe replace the clutch every 20 years.
|
|
|
|
fierofool
|
FEB 26, 10:10 PM
|
|
Should the 2.8 give it up, the BM 3.1 and 3.4 engines are essentially the same blocks. Everything from the 2.8 bolts directly on. The 3.1 starter is on the correct side but the 3.4 will require drilling and tapping mounting holes on the other side using Rodney Dickman's starter relocation tool.
The 3.1 has the same HP as the 2.8 but more torque. The 3.4 has more torque and HP. My 87 has the 3.4 and my 86 has the Lumina APV 3.1.
With the automatic, you're locked into the one transmission without doing some mods to accept other automatics. With the manual transmission, you have a choice of 3 manuals that only require shifter, cable, transmission mount and slave cylinder bolt-ins.
You're registered on the Georgia Fieros message board. Come down to Marietta for the March 11 meeting and you can see a wide selection of options.
|
|
|
|
belldan
|
FEB 27, 09:55 AM
|
|
|
Thanks to everyone who responded to my questions regarding the automatic transmissions and 1988 part availability. I really appreciate it ! ------------------
Danny Bell
|
|
|
|
82-T/A [At Work]
|
FEB 27, 11:29 AM
|
|
| quote | Originally posted by belldan:
Hello Everyone! I'm in the market for a Fiero GT and would like to know if the V-6 engines and automatic transmissions are reliable. I really appreciate any and all information. Also, I read that parts for the 1988 model may be hard to find so kindly advise if what I read is or is not true. Again, thanks very much for taking the time to respond !
|
|
Off the cuff response, I think the Th125c is absurdly reliable. The only issues I've ever heard of people having, is the torque converter no longer locking up (usually not a mechanical but a sensor / switch problem).
I'll put it this way (no judgement). When I first got my Fiero back in 1996, I had the GX3, which has the 3.33:1 final drive (the highest gearing). MANY times... I ran at sustained speeds of 120 miles an hour. MANY times, I would put it in neutral, floor it, and then shift it quickly into drive to do a burnout. I did this MANY MANY times... before I was told (and learned) that this is the worst possible thing you can do for an automatic transmission.
I've beaten the **** out of that transmission... flooring it constantly... like, at every light. I was 18 when I got it, and stopped driving it when I was 21 becuase the engine blew and life took over. The only thing that in fact I never had problems with, in all 7 of the Fieros I've owned... was the automatic transmissions.
Per Patrick... yes, the cars are definitely 40+ years old now. And one of the things that happens is that the individual clutch disc material will degrade and break down. If you plan on running an older car at this point, I would recommend a rebuild, but they are solid, and very reliable.
Many people upgrade to the 4T60 though, because you get an extra gear, and better gearing through the individual gears. It's not a difficult swap.
EDIT: I was just corrected that the gearing for 1st, 2nd, and 3rd between the Th125c and the 4T60 are the same. The 4T60 of course just provides an additional gear for cruising which obviously helps reduce engine RPMs on the highway. I had a 4T60E in my GrandAm behind a TwinCam LD9, and loved that transmission.[This message has been edited by 82-T/A [At Work] (edited 02-27-2023).]
|
|
|
|
theogre
|
MAR 01, 06:42 PM
|
|
| quote | Originally posted by 82-T/A [At Work]:
EDIT: I was just corrected that the gearing for 1st, 2nd, and 3rd between the Th125c and the 4T60 are the same. The 4T60 of course just provides an additional gear for cruising which obviously helps reduce engine RPMs on the highway. I had a 4T60E in my GrandAm behind a TwinCam LD9, and loved that transmission. |
|
Not quite.
code:
RPO Transmission 1st 2nd 3rd 4th 5th Reverse Final
MD9 THM 125c (3T40) 2.840 1.600 1.000 2.067
ME9 THM 440-T4 (4T60) 2.921 1.568 1.000 0.705 2.385
On top of other gear changes between 2 units.
See my Cave, Gear Ratio
|
|
|
|
sanderson231
|
MAR 01, 10:45 PM
|
|
Everyone has their own opinion but I would not pass up a nice 88 GT due to fear of parts availability:
The 88 brake master cylinder is not available but the 84-87 master cylinders are. The difference between them is 1/16" of an inch different piston diameter. Most people would have a hard time telling the difference
The Fiero store has remanufactured brake calipers. Rock auto has caliper rebuild parts including the piston. If push come to a shove there are options to install calipers from other vehicles
The brake rotors are readily available
Rock Auto and The Fiero Store have struts and shocks
The Fiero store has polyurethane bushings for front and back
Rock Auto and The Fiero Store have ball joints
The sealed hubs for the front are not available but Rodney Dickman sells greasable hubs that use tapered roller bearings.------------------
formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged
|
|
|
|