The truth-straight to you..the 4l60 is a junk transmission..it has an internal oiling problem..factory parts.transmission..came with defective parts..from the get go..
One of the biggest.defective part.is the sun shield.among others.if you have a rebuilt one.with the up graded parts.and there are lots.that need to go in one of them..
It may last awhile.you sure as hell.do not want to put one in a 4wd..no way no how.when that sun shield goes.you have no.1-3 or reverse..
It will cost you more then it is worth.to get one rebuilt.4l80e was a little better.came in bigger vehicles and the hummers.they have done away with these all together..
I think.even knew cadilac.transmissions.had to be pulled out by the dealer.for internal trans problems.my 1996 espress van.is on the third..4l60e.i had this trans.gone through by a chevy dealer trans guy..
So far it is holding up.but i would not tow.anything with it.it does not feel strong.i know some guys were changing out the autos for..manuals..hanging a clutch pedal..
Even in the caprices..but you could look in to a 4l80e..make sure its parts.were changed out.one of the replacement parts.is called the beast sun shield.did i say.my van only has 142,000 miles.
It has the 350r vortech.beautiful roller motor.runs like new.trans is the weak link.
I hate to burst your bubble there wheelman BUT.
The only oiling system problem they have is the same one ALL TRANSMISSIONS HAVE "shift firmness" which like every transmission is improved with a shift kit.
The 4L60e is the same as the 700R4 if it was JUNK then they wouldnt have used it for so many years. YES they have made improvements to them over the years, but so has every other transmission on the market.
Personally I think these transmissions have gotten a bad rep from inexperienced people having problem's with them from ABUSING them.
Now I am not saying that you are abusing yours intentionally. They are rated for 6,000 Pounds, so when they put these transmissions in VANS, EXTENDED CAB FULLSIZE PICK UPS they were doomed right from the start, Top that off GM put 3.42 gears in alot of those same vehichles. Most people learned the hard way to NOT tow with them in Overdrive, BUT those same people didnt realize that towing did NOT just mean hooking up a trailer. It also ment hauling, Which is 1 reason why the newer ones have a TOW/HAUL mode. Even then alot of people refuse to use it for fear of burning a few extra gallons.
They say 9 out of 10 Transmission failures are due to heat, That is NOT the transmissions fault. It is the engineers that built these vehichles The Coolers they use are a joke running them thru the radiator, then on "Heavy Duty" models the added another small cooler in front of the Radiator, when they should have used a BIG external cooler from the start.
YES there are internal component failures in these Transmissions, BUT It is NOT that exspensive to completely rebuild AND UPDATE these transmissions.
The "E" in 4L60E stands for electronic. Some people dont think it was a wise decision on GM part to go to electronically controlled, I for one actually like it, for reasons of my own. The biggest thing you have to remember is that the Transmission's electronics are supplied 12 volts from a the ignition switch 9Which are notoriouse for failing that in return causes Transmission failures).
The Electrons are controlled from the Computer sending a GROUND signal to the transmission to operate the solenoids and switches. So when the computer does not get a good ground then it passes the bad ground conditions off to the transmission which causes failures.
The only hard parts that are ever really updated, are the sunshell, and the sprag cluches (1 way bearings) they were desighned poorly but have since then been updated, oh and the 4 planet planetary gears, they were also updated to the 5 planets in the 4L65E. The other updates that are done to the Transmission are updates with the shift kit and worn valves in the valvebody and pump.
4L60E IS NOT A JUNK TRANSMISSION, IT WAS JUST INSTALLED IN THE WRONG VEHICHLES, WHICH HAVE GIVEN IT A BAD NAME. Even after some rebuild them they fail even with the updates, My bed it 9/10 of those people did NOT even install new Bushings either or the BIG cooler.