Accepted Answer

Hello,
Sorry to hear about your problem.

4L60-E transmission have numerous converter overheat and lock-up complaints related to valve bore wear. These include no lock-up or lock-up immediately after 2nd gear when fluid warms up. Frequently the solenoid will have no control over the valves position. These complaints are usually created by excessive pump bore to valve clearance. Often converter feed oil will leak past the OEM spool, which added together with orificed signal oil, will be more than the solenoid can exhaust. This may completely stroke the valve into the lock-up position and create a no power or no brake cancel condition. Oil cross leaks may float the valve into a midway position and restrict cooler flow, which burns up the converter.


A worn 3-4 relay / 4-3 sequence valve body bore can cause a no 4th gear situation in a 700R4 or 4L60E. Due to the constant valve oscillation, wear occurs at the 4th accumulator circuit. This can lower 4th gear pressure by as much as 20-25 psi, resulting in lower servo apply pressure or no 4th gear. Leakage also occurs at the end plug, due to valve hammering. This allows 4th signal oil loss which can result in a no 4th gear situation.

below is the sk 4l60e shift kit made by transgo, it will fix most problems with the 4l60e
if its time for n overhaul you can have this kit added to a new one as well.
my father used this kit on his 4l60e and reports that it fixed his o/d and 1-2 bang shifts.
he installed it himself, but I don't recommend this unless you have worked on transmissions before.

SK®4L60E 4L60E & 4L65E 93-05 Cadillac Escalade, GMC Envoy, YukonXL 5.3L, 6.0L, ChevroletAvalanche, Trailblazer, Blazer, Suburban 5.3L,6.9L, Oldsmobile Bravada Fits 4L65E Except Hybrid Corrects/Prevents/Reduces: FIXES Code 1870 Trouble light & Hard 1-2 shift. No lockup or 4th. Fixes harmonic bounce that wears out pump and valves and causes shuttle shifts. Fwd and L/R clutch burnup; 1-2 bump; double bump; slide-bump.Has new design Isolator/Conv Valve that works Perfect in worn bore w/o special tools or machining. Lets you build real winners Easy and Fast.

Hope this helps you out!!

Thanks,
XXXXXX X. XXXX

Expert:	Joshua
Pos. Feedback:	97.4 %
Accepts:
Answered:	10/21/2007

GM Performance Tuner

Extensive Training in GM engine management systems & performance Tuning.