I know nothing about these cars. How hard (and expensive) is it to replace a bad automatic transmission in an 88 Corvette? I doubt that a manual swap is an option.
I know nothing about these cars. How hard (and expensive) is it to replace a bad automatic transmission in an 88 Corvette? I doubt that a manual swap is an option.
You do have a vehicle lift, don't you?
Accessibility to anything on a C4 is a pain in the posterior, but it's all standard GM fare so it shouldn't be that expensive.
However check that the digital dash is working correctly, if it's got the green backlight (square) one, you might have to factor in repairing that, too.
Still no lift...
Skip the vette and buy a lift instead.
That's the more likely scenario...
Yes, I don't think you want to swap a trans on a C4 without one.
just dig in and do it... it's just a 700r4 bolted to the back of a 350- how bad can it be? on the other hand, it is an 80's GM product, so there are hidden ground wires everywhere that you won't remember to hook back up and won't be able to figure out why things don't work properly when you get it back together..
I did a swap, 3 times, on my C5. I cant imagine a C4 being worse. Different sure, but worse, nah.
Get yourself two pairs of truck jackstands and get that rig up in the air, at least 18", and get a real trans jack, not a floor jack and a board. A helper wouldnt be the worst idea either.
BoxheadTim wrote: You do have a vehicle lift, don't you? Accessibility to anything on a C4 is a pain in the posterior, but it's all standard GM fare so it shouldn't be that expensive. However check that the digital dash is working correctly, if it's got the green backlight (square) one, you might have to factor in repairing that, too.
I've found the c4 a dream to work on in comparison to the pair of 944 turbos I owned.
Cribbing blocks.
93gsxturbo wrote: I did a swap, 3 times, on my C5. I cant imagine a C4 being worse. Different sure, but worse, nah. Get yourself two pairs of truck jackstands and get that rig up in the air, at least 18", and get a real trans jack, not a floor jack and a board. A helper wouldnt be the worst idea either.
these are tools that everyone is supposed to already own- i have 2 sets of 6 ton jackstands that go up to 24" high and a 3.5 ton jack that will get a car up onto them- so the assumption is that those tools are already in the garage of the OP...
In reply to novaderrik:
I think of 6 ton stands as standard, 3 tons are for quick stuff like oil changes or situations where I'm not really under the car. 12 tons are the stand you're looking for. Or an inspection pit.
You kind of don't want to do a manual swap; the ZF6 isn't cheap and there's everything else: an ECU, a pedal cluster, manual trans bellhousing, clutch master & slave, shift panel, shifter, etc.
Keep in mind that you need to support the engine while the trans is out. You do not want the engine to rock back sufficiently to rest on the firewall as ancillary components can be damaged. I've used an engine hoist for this because it's adjustable while you're taking the trans out. More on that in a bit. It's been a few years, so this is from memory:
Before starting, buy replacement studs and nuts for the exhaust manifold. You will be removing the exhaust aft of the front Y and the studs are designed for single use. They will usually break. Also, drain the trans but put the pan back on.
Before you raise the car, disconnect the trans dipstick tube brace in the engine compartment. Raise the car. Support the engine. Remove the exhaust. Remove the driveshaft, being careful with the u-joints if you plan to remove them. You do not want to drop the ujoint caps or you will be making a run to the parts store before you reinstall the driveshaft. I've used tape to hold the ujoint together while disconnecting its tiny brackets.
Disconnect the speedo cable, shift linkage, trans cooler lines (if equipped), flexplate dust cover, and dipstick tube from the trans. Place a trans jack under the trans to support it. Next, remove the "ladder" that forms the car's spine by connecting the trans tailshaft to the rear diff casing. It is secured by bolts that point "up" and nuts on top of the ladder. Slide a box wrench across the ladder to capture the nut and a socket wrench on the bolt. You will have to rotate the ladder to get it out, and may have to slightly lower the trans for clearance.
With the exhaust, driveshaft and ladder out, the trans drained and all connections detached, you are ready to begin removing the bellhousing perimeter bolts. The lower ones are obvious. To access the uppers you may need several feet of extensions and a wobbly extension. You will have to lower the trans slightly in order to gain access to the upper bellhousing bolts. A pry bar helps separate the bellhousing and guide pins. The torque converter usually stays on the trans input shaft and it will be full of fluid, so the whole assembly is heavy - use a trans jack and drop it carefully.
It's not a bad job; two guys should be able to do it the first time in under two hours. Keep in mind that the Corvette 700R4/4L60/4L60E has a unique tailshaft housing with provision for mounting the ladder. Other than the tailshaft housing, any like trans will work, and the tailshaft can be swapped to it without a big fuss.
Cotton wrote:BoxheadTim wrote: You do have a vehicle lift, don't you? Accessibility to anything on a C4 is a pain in the posterior, but it's all standard GM fare so it shouldn't be that expensive. However check that the digital dash is working correctly, if it's got the green backlight (square) one, you might have to factor in repairing that, too.I've found the c4 a dream to work on in comparison to the pair of 944 turbos I owned.
I'm glad you do. I found it to be a royal pain in the ass.
I R&R'ed the 4+3 in my '88 twice. (It was bad when I got the car, then the replacement was defective) Get the car up as high as you can and it's no worse than any other trans swap. A set of beam plates from ZF Doc makes the job easier.
http://zfdoc.com/c4beamplate.htm
There is a measurement for putting the beam back on the trans, plate kit comes with guides to make it easy. (or just use the measurements to make your own)
Bobzilla wrote:Cotton wrote:I'm glad you do. I found it to be a royal pain in the ass.BoxheadTim wrote: You do have a vehicle lift, don't you? Accessibility to anything on a C4 is a pain in the posterior, but it's all standard GM fare so it shouldn't be that expensive. However check that the digital dash is working correctly, if it's got the green backlight (square) one, you might have to factor in repairing that, too.I've found the c4 a dream to work on in comparison to the pair of 944 turbos I owned.
It's not my favorite car to work on by any means, but it's a cakewalk compared to the 944t imo.
If you like manual transmissions, I would suggest to do a manual swap. Doing an auto to a manual swap is probably most popular with Camaro/Firebirds, Mustangs, and Corvettes. A few extra things you do need compared to regular service would be an extra set of hands. I helped my brother upgrade the trans on what was formerly his Camaro and it wasn't too difficult. Accessing some of the bolts that hold the bellhousing to the engine are probably a challenge.
You'll need to log in to post.
