I have a 91 4L60 that I am rebuilding right now and I have some questions for the transmission guys on here. When I pulled the thing apart I found it had been rebuilt with a 4L80-E kit could this have caused any damage? It has a sun ring gear around the output shaft floating losely between the governor grooves and the speed ring gear. Does this belong here? The case has a few scratches (enough to catch my fingernail) how deep is too much? It's missing the 5 Boost Springs. Are these dealer only parts or can I order them online somewhere? (I cant seem to find them) How many Check balls are supposed to be in it? My manual said 4 (I think) one in the accumulator housing and three under the throtttle body, but this thing had about six check balls floating around in it when I tore it apart. And finally what are some tried and true performance mods for this transmission? Thanks for any help!
A 4l80 is a completely different animal in many different ways. They do share a few parts, though. My sugestion for Build info and parts is this- Performance Transmission Center. Google it-They will have what You need. Thier tech guys are bad asses.
jchav62: The 700r4 was renamed 4L60 in 1990. You are thinking of the 4L60-E in 93 which changed the hydraulic logic shifting system over to an electronic one. I checked my 2-4 band again and it did say 4L60-E. Oops, I read it wrong! Why would there be a metal gear around the output shaft between the governor splines and the speed gear? Did someone FUBAR this rebuild or does it belong on some models?
Get the "beast sun shell" a corvette servo and some upgraded clutches/bands They can be built up to handle some hefty HP http://www.4l60-e.com/ should have all the parts you need
there are 2000 rev's per mile 4000 rev's per mile and i meant 40 rev for each driveshaft revolution My mistake
you are confusing two different items. The reluctor wheel in this discussion produces 40 pulses per revolution and 4000 pulses per mile is the calibration GM uses. Some after market gauges are calibrated for this GM spec this too. If you go out and google this info , you find 2k , 4 k , 8k , 128k figures.. that is all fine, in discussion of the whole systems on certain year groups. This 1991 trans could be a 2000 pulse per mile unit , but it should not be a reluctor wheel... the early electronic units were usually gear driven by the common known speed-O gear. These speed sensors can be hard to locate for an OEM unit when needed. I have seen some folks install a speed-O bullet with plastic gear into a tranny with this metal reluctor wheel and then wonder why the speed-O does not work.
Okay this is the ring I am talking about. It does look like its a reluctor gear, but should it be on a 91? I pulled the numbers off the case and it is in-fact a 91. Am I correct in assuming this may be a frankenstein transmission? Would it hurt if I removed it to use only the red mechanical speed-O-gear with the correct housing? Thanks!
That looks like it has both the reluctor ring and the gear drive for the "normal" speedo (electric or mechanical). That is weird. As for a 91 having the reluctor, some 91's did come with them (I think S10's and Astro vans for example) but I'm not sure what all did or did not. Sorry I'm not more help.
You don't need them both. If you want to remove it and just use the gear to drive a cable go for it. Your speedo cable drive does have a gear also right?
I am pretty sure there is six check balls above valve body. I have rebuilt a few of these, but never new they called them 4L60 until '93, i learned something today.
Thanks for all your help guys! I dont have a speedo housing yet and was just going to go with the mechanical gears to try to save a couple of dollars. This website is priceless! I've learnt more about cars in six months than I have in my entire life by doing this build!
I'm actually showing 7 check balls in the valve body, 3 above the plate in the case, and one in the input housing. Not a trans guy (just enough to pass ASE), but I do have the GM technicians guide for the 4L60E from when I was in school in 91. This is the book if want to know this trans. Let me know if there is anything specific you'd like to know. Also, the mechanical speedo drive was added to the 4L60E shaft for the 91 application. Tim
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