gsjimmy

OK, I'm not a transmission guy. This trans is driving me nuts

I am having issues with the 4l60e. When first started I had movement through the trans to the rear wheels. Now nothing. Been fighting this all week, so I finally dropped the pan to check the internals.

Symptoms say "Front Pump fail". So tonight I started the truck after checking the oil level on the stick (way above full hot). With the truck running I puled the stick and had a level of full cold (level dropped). So, that would say that the pump is working. So my next step was to drop the pan (and make a mess on the floor) to look for anything out of place, junk in the pan.

Pan looked fine, a little bit of gray in the bottom (not bad at all), magnet had a little gray material, again not bad.

I also ran the fluid through paint strainers found some crap in it, but could have come from the outside of the pan when I dropped it.

I checked the selector and it moved fine into all gears. No linkage in the pan, everything appears as it should. So what is going on?!?!?!?

I really don't want to tear it out again.

The truck was driven into the shop last October as a daily driver. No trans related issues. When I got the truck in '09, was told that the trans had been replaced at the dealership around '05. All stock GM 4L60E, 2wd. I did have issues getting the engine & trans to mate up. Turned out to be the wrong bell housing on the trans (LS1 converter & S10 trans) Got everything together. No I didn't force it together with the bolts. Once there was resistance I stopped and took things back apart.

When first assembled, had a small leak at the upper fitting, I knew that there was oil moving in the trans. I had shifted the truck into gear to make sure everything was OK (driveshaft moved, wheels turned). But I had a crazy light show going on in the dash. No gauges working, lights going off & on, same with the headlights. Turned out to be a misplaced ground wire on the harness (problem solved). I also replaced the neutral safety switch due to the keyed switch not engaging the starter (fixed).

No weird noises, Can see the motor lug down of the tach and by ear, when shifted into gear, but still nothing is moving. Trans is full of fluid (drained right now as I look for the source of the problem).

What am I missing here? Could the multi-switch be out of adjustment and causing all of this? Truck starts fine in P and N, fluid is new and full. No chunks of gear material from the pump in the pan, no disk or band material in the pan. Linkage moves freely, shift cable is fine.

Docrocket1967

iTrader: (1)

Have you tried running a pressure test?

gsjimmy

Not yet. What line pressure and where does the gauge go?

performabuilt

iTrader: (25)

Reading Did you simply change the bell housing to the LS type ? If so that is the issue the depth is different or if you put he LS converter and bell on the S10 trans the input shafts are different so no engagement will be possible to make that swap you have to change input shaft, pump stator , bell and converter

gsjimmy

So the quick fix would be to swap out the bell to the original and run the 4.3 converter. I already have the spacer. That also would mean I elongate the holes in the flex plate.

The other option would be to change out the trans completely to a V8 unit.

mrvedit

Without knowing all the details, that sounds like a plan.

It is very unfortunate the GM did not change the part number to e.g. 4L62E when changing from the LT-style 298mm input shaft to the LS-style 300mm input shaft. The bell housing and converters are completely different between them.
Of course if GM had done everything "right" this forum wouldn't have many posts.