Mar 23rd, 07, 3:15 PM
I am looking to swap out my turbo 350 for an overdrive transmission. I was under the impression that 700r4 and 4l60 were the same transmission. The parts guy at the local chevy dealer says that is not true. He said the 4l60 has different internals and is a better transmission. I am getting the GM Performance Parts 350 HO turnkey from the local Chevy dealer, but was planning on getting a Bowtie Overdrive 700r4 level 2 transmission. He says I should look at the 4l60 option. I am not exaclty sure but it sounds like there is a kit you use to make a 4l60E operate without the electronic interface. Any opinions or clarification on this topic would be appreciated.
Mar 23rd, 07, 4:21 PM
the 700 is a 4l60.in 93 the700/4l60 became 4l60-E[electric shift].i would build a 88-92 700 for your car.you can upgrade your parts inside with a beast sunshell,wide 2-4 band.alto 3-4 clutch pack,corvette servo or billet servo and a shift kit. this will hold 450-500 horsepower and it shifts off a cable. if you installed 4l60-e you would have to have computer and other sensors for it to work. the parts guy is confused on not being the same. also the 700 is exactly 3 inches longer and you will have to do a mount or crossmember modification. hope this helps greg
Mar 23rd, 07, 5:31 PM
Parts guy called back with prices and I got some clarification on what he meant.
He said the 700r4 to stay away from are the ones that are pre 1987. He said this may not be official but he considers:
1987 and earlier to be 700r4
1988-1992 to be 4l60 and
1993 and newer to be 4l60e.
The kit he was talking about is for the 4l60e. The kit allows you to use the 4l60e without the computer. It probably does not matter becuase the kit itself cost between $700-$1000, not counting the transmission.
Mar 24th, 07, 12:07 AM
If you have the money go with the newest 4l60e you can afford. You will have to have a computer controller but this is a good thing. You can fine tune the tranny to just the way you like it. Also, if you run the TCI computer you can use the same controller if you upgrade to a 4l80e down the road.
The main reason is that all the 700r4's are pushing 20 years old now and finding one in nice shape with low miles is rare. Also, the later 4l60e has a ton of improvements that you have to do to the 700r4. Not that the 700 is bad, but it requires a ton of band aides. Now so does the 4l60e, so go with the 4l80e if you want to install it and never worry about it again.
Pretty much the 700's ran up till 92 and then went electronic in 93. There are someoverlaps, but you want to avoid the really early 86 and before 700's. They can be build to match the later ones, but that requires more upgrades than they are worth to begin with.
Like Greg said, plan on shortening the driveshaft 3 inches or so. Tranny mount should be the same, just slid back a bit.
Oh, and one thing I never hear mentioned...some 700's and I think pretty much all 4l60e's use electronic speedos. Be prepared for this and it is not a huge problem in these trannys. For the 4l80e it is an expensive thing to overlook, main reason I have been driving mine 2 months with no speedo...
Hope this helps, do a search here and you will find some great info on both of these trannys. Either one will make you much happier than the 350 and no overdrive.
Mar 26th, 07, 11:50 AM
I'm perfectly happy with my 700R4 (4L60). These guys are right on. If you go non-electric shoot for as close to 92 as you can. They have better parts as well as the higher spline count. Definately check out upgrades for internals just as Greg5436 said. Some guys are now even upgrading to cerain 4L65 internals to overcome weaknesses too.