Hi, i was wondering about the 4T60 swap. I have an 88 GT with the auto. I've read a lot about it and have mixed feelings about it. Can it be a direct swap if all the parts are available or is there more to it? I want to the car looking as original as possible. I also don't want to mess with the frame if at all possible.
Hi, i was wondering about the 4T60 swap. I have an 88 GT with the auto. I've read a lot about it and have mixed feelings about it. Can it be a direct swap if all the parts are available or is there more to it? I want to the car looking as original as possible. I also don't want to mess with the frame if at all possible.
If you didn't want to cut / weld, then you could probably beat the piss out of that area with a hammer, but quite honestly, cutting and welding the area is your best bet.
Everything else is very easy... just plug & play with various OEM parts.
I just went through this swap for my '86. It will make your driving experience much more bearable and enjoyable at speeds greater than 45 mph (must reach 45 mph to shift into 4th). If most of your travel is less than 45 mph, then you probably will not benefit much since it's pretty much like the TH125 at those speeds. I would do it again in a heartbeat. Aside from the cradle modification on the 88, it should be a very easy swap.
I just did one on a 1986 which is easier compared to the 88, but still not a hard swap to do. What's more difficult is finding the specific governor, the rest is pretty easy to find. It is so smooth at highway speed now. just hums along. great swap to do.
------------------ 1986 Fiero GT Fastback 3.4Lpr with 4T60 1979 Naked Honda Goldwing - sold 1983 Honda Goldwing 1100 Interstate
Well, if i ever sell it could i put the original transmission back on the cradle? I live fairly close to the highway and 70 at 3300 rpm's are not very good. I want to have a good cruiser, but want to be able to beat a camaro or mustang off the line. I thought about a 3.06, it sounds like the best of both worlds. What would you guys recommend? Plus i want to drop in a 3.4 and maybe turbo someday.
I would think the 3.06 is a good idea. someone with way more knowledge than me can chime in, but I'm not sure the 1-2-3 gearing is all that different between the 125 and the 4T60 it's that 4th gear that is the difference maker.
for what's it's worth I really like the little bit of added oomph of the 3.4. just is all around a better motor, but if you want something that will really go you'll be disappointed with the 3.4. Judging by your comment you might turbo, then my opinion would be do the 3.8. skip the 3.4. which also generally means you need to reconsider the 4T60.
------------------ 1986 Fiero GT Fastback 3.4Lpr with 4T60 1979 Naked Honda Goldwing - sold 1983 Honda Goldwing 1100 Interstate
I would think the 3.06 is a good idea. someone with way more knowledge than me can chime in, but I'm not sure the 1-2-3 gearing is all that different between the 125 and the 4T60 it's that 4th gear that is the difference maker.
for what's it's worth I really like the little bit of added oomph of the 3.4. just is all around a better motor, but if you want something that will really go you'll be disappointed with the 3.4. Judging by your comment you might turbo, then my opinion would be do the 3.8. skip the 3.4. which also generally means you need to reconsider the 4T60.
I don't want to ruin the originality of the 88 GT. I would do the 3.8 in a lower year fiero considering the 88 GT is really unique. I plan on finding both a 4t60 and a 3.4. So I only have to drop the cradle once.
I thought about the 3.8 in the past but I don't have the funds to do one. Maybe another time when i do have the funds.
The 3.8 with 4 speed auto is a difficult swap,it is time consumming,never believe this swap is easy we have some club members performing this swap now.. when purchasing a 4t60 make sure you get a good one ,,these are notorious for being bad there is nothing wrong with the 3.4 performance .. the 3.8 buick is as good an engine, as the 4t60 auto is bad,make sure you get a good one ! all the closed auto Transmission shops you see across America ,were kept open by bad G.M.4t60,s untill they were few !! the T125 is far superior to the 4t60 for reliability, it just sucks on the expressway,you can change the gear ration by swaping the T125 3 speed chain & sprockets the only additional Fiero that will have value is the 88 T top,
[This message has been edited by uhlanstan (edited 11-08-2013).]
The 3.8 with 4 speed auto is a difficult swap,it is time consumming,never believe this swap is easy we have some club members performing this swap now.. when purchasing a 4t60 make sure you get a good one ,,these are notorious for being bad there is nothing wrong with the 3.4 performance .. the 3.8 buick is as good an engine, as the 4t60 auto is bad,make sure you get a good one ! all the closed auto Transmission shops you see across America ,were kept open by bad G.M.4t60,s untill they were few !! the T125 is far superior to the 4t60 for reliability, it just sucks on the expressway,you can change the gear ration by swaping the T125 3 speed chain & sprockets the only additional Fiero that will have value is the 88 T top,
3.4 is the way that I'm going and having been searching for a while. I can't seem to find a good deal on one, the people want to much for a high mileage engine that needs to be rebuilt. I found a lot of 4t60's in the junkyards, but how much would it cost for putting in some performance parts? If any? I know on some of the of the discussions when they get the 4t60 rebuilt the mechanics forget something which prolongs the swap and creates issues for the owner thinking it's their set up.
I know I'll have to rebuild both engine and transmission, I can do the engine and put in what I want but the transmission is something I can't do so I'm going to have to have someone do it.
I would disagree with some of the statements above about the 4T60 not helping much below 45. I had one swapped into my wife's 88 Fiero along with a stock 2.8. What a change in a lot of ways. 1st gear is a lot lower in the 4T60 so it gets out of the hole a lot better with it in the car and of course the top gear really brings the RPM's down on the highway.