Is my tranny done?

[littlejimmythatcould]

I have a 1996 1/2 ton 2wd with a pickup with a 4L60E (I think) that I use as my tow vehicle to move my junk around. The truck just turned over 100,000 miles about a month ago. I changed the tranny fluid in it today because I was planning on doing some long distance towing these next few weeks. Now, my 4 gear and 3rd gear are acting up (slipping) 4 gear is pretty much gone, I had to drive it back from the shop in 3rd at 3000 rpms down the high way. And if I manually shift it up into 4th OD gear the motor starts winding out and that's not good. My passing gear and stuff still work and it can still be romped on but down the highway OD is a no go. Could some air or something be trapped in there not letting it shift? Oh yeah, the transmission fluid wasn't bad looking just a nice burnt red color (that's the only way I can discribe it) but it wasn't bad looking and didn't smell burnt. The magnet in pan had some really fine black deposits on it but no chunks or shavings. I wish I would have just left it alone. Any and all help would be very appreciated, I'd llike to get this truck up and running in a week and a half (if possible) so I can tow my jimmy to go wheelin' for its first time. Has anyone else experienced this and how did you fix it? Thanks.

 

[sweetk30]

sounds like its going out.

 

[danny7139]

I've heard to leave alone tranny fluid after 100,000 because of problems like this happening for getting clean fluid. I just changed a 200,000 700r4 and luckly it didn't hiccup for it. Did you change the filter also? If so are you sure the filter is on all the way. Check for leaks around the pan gasket.

 

[K5er4Life]

you didnt do nothing but a oil and filter change right? Havent messed with the valve body, ie. shift kits or anything? The fine metal shavings on the magnet are normal, I have heard of trannies, 700's and 4l60's in particular acting up after oil changes. This seems to happen when the fluid is old and for some reason the trans doesnt take the new fluid well. Maybe someone can elaborate as to what causes the clutches to suddenly start slipping after a fluid change.

 

[HarryH3]

First, STOP driving it! If the problem is just low pressure you'll do more damage by driving.

Are you sure that you installed the new filter properly? Those transmissions have a VERY tight fitting filter seal up in the valve body that seems to always get stuck in the hole. If you didn't get the old seal out before installing the new filter then you could A) have a leak or B) the filter is pressed against the pan, restricting the flow. Either way, the trans doesn't get enough pressure to operate properly.

I would drop the pan again and look closely to see if the filter is installed correctly.

 

[littlejimmythatcould]

Yeah I pulled out the old the old filter seal and installed the new one and pushed the filter in as far as it would go. I changed the fluid at 75,000 miles (when I bought the truck) and I changed it again (this time) at 100,000 miles. The only thing I could think of is maybe I have some air pockets or something in the valve body from having it open for a while, it took me about an hour or so to get the filter seal out and the new one in. 1st through 3rd are good it's just that overdrive gear that really went out, but without that gear, I might as well have a TH350 in the thing! My personal feeling is that after 130,000 to 150,000 miles don't touch the tranny fluid. So this was probably to be my last change on the fluid. I was just trying to be responsible and take care of my junk. So.... what's a good price on average to rebuild the 4L60E? thanks for the responses so far.

 

[NateInChandler]

Did you by chance pull the crossmember back away from the pan for a straight shot down with the pan?? Ive seen guys try to wiggle the pan out with the crossmember still in stock location (it sits almost a 1/4 away from the pan) and they break the Solonoids on the back of the valve body.. also, the filter should plud into the Pump and not the valve body, the 4l60Es have a reusable filter gasket that is forced into the pump before installing the filter when the tranny is assembled.. Id pull the pan and re-check everything.. Nate

Also, i wouldnt drive it in OD any more than you half to, 4th gear and lockup work together to supply lube to the planets and if your having problems with it you could cause more trouble.. just a fyi.. nate

 

[1985_K5_Silverado]

You could screw a trans pressure tester gauge into the main pressure tap, then try the "2nd oil" tap, then the "3rd oil" tap and then the "4th oil" tap. Refer to the factory shop manual (or a similar ref book) to see what pressures you should be reading at each tap at various throttle positions.

If your pressure is inadequate in some or all gears, your clutches can slip and grind the plates to paste in short order.

 

[littlejimmythatcould]

I did pull the cross member to drop the pan it is near impossible to change the fluid without moving it. I wonder if I'll be alright driving it in 3rd gear so it shifts 1-2-3 and then not into OD until I can get it to a professional. Those gears seem to work fine. I just wanted to maybe get an idea of what might be going on. But I think it's probably time to rebuild it.