4L60E experts... couple maintenance questions!

[Chris B.]

So I'm doing some maintenance on my old girl(1997 GMC Sierra 85,000 total miles). How sensitive is the 4L60E to being slightly overfilled or under filled? I dropped the pan and changed the filter and fluid. It took about a gallon or a bit more to fill it back up. I'm with in 8oz of being spot on 100% filled correctly. The level on the dip stick was about 3/16" over the max full line when checked fully hot and idling. I drained out 4oz and it is a hair less then 1/8" below the full line now. I may add 1oz and keep heat cycling and checking till it is exactly on the max full line. Just wondering if being a little(8 or so ounces) under or over full is going to cause any issues?

Also I flushed the tranny 7 years ago with a flush machine. This time when I dropped the pan the fluid looked bran new! Just wondering if the 7 year old ATF was still good or if it was time to change it because of age. It only had 10,000 miles on it because the truck sits garaged most of the time.
I'm planning on doing another flush with the machine to get 100% new ATF in the entire transmission just to be on the safe side.

Here is what the filter and fluid looked like. Filter has never been changed before and is factory:

 

[69GTX]

That all looks real good to me. I doubt the Trans Fluid changes much just due to age as long as it doesn't absorb water through an open dip stick tube or something. But no harm in a 7 yr flush. My trans filter was 14 years old when I just changed it at 70K miles. It looked a lot dirtier than yours. You might not even need to do a flush as many cars go 150K miles/10 yrs on factory fill. You only have 10K miles.

Hard to say how sensitive they are to oil level around the "normal" mark. A few ounces either way is probably ok. Slightly less is better though imo. Just dial in your level over the next few weeks to hit the full line when hot.

 

[Chris B.]

I figure a pan drop got about half the old fluid out so I was thinking of doing another flush to get it all back to 100% new fresh ATF. But it does look pretty darn clean as is.

 

[NYEngineer]

You're very fortunate. I had a 98 Yukon back then and had NOTHING but trouble with my 4L60E. I didn't tow with the truck or anything.

I almost never bought another GM product again but I took a chance on an 09 Suburban and the 6L80E has been stellar.

 

[Killer223]

i think it' fine, my 94 yukon had over 300K on it factory trans, with a pan drop and fluid change every 45K.
keep the fluid in good order, you should be fine.

 

[dlundblad]

Does it need to be in gear or neutral for checking?

 

[Gasbuggy]

I know that trans well. The fluid looks brand new. Don't change it again for 35-40k. Don't worry about a slight overfill, plenty of guys out there on LS1tech and other GM forums doing that on purpose.

 

[LeakySeals]

Do you have cooler lines? I did an exchange that way last year. Its like a brake bleed, you keep adding and purging until the fluid is clear. Sure beats a messy pan drop which only gets +-30% of the fluid.

 

[Kira]

I can tell you a 4L60E in a neighbor's 2001 Camaro (shallow pan-your truck might be fitted with the deep pan) was 30 oz. low of fluid-likely never checked from new-and was freaky slow in engaging.

All was well after bringing her back up. They sold the car to Camaro freaks.

You wouldn't add some TransGard red to the old girl's fluid?

 

[Chris B.]

Originally Posted By: dlundblad
Does it need to be in gear or neutral for checking?


Procedure is to get it hot and then park on level ground and run the shifter through each gear for 4 seconds and then put in park and idle for 3-4 minutes and then check dip stick while running.

 

[Chris B.]

Originally Posted By: Kira
I can tell you a 4L60E in a neighbor's 2001 Camaro (shallow pan-your truck might be fitted with the deep pan) was 30 oz. low of fluid-likely never checked from new-and was freaky slow in engaging.

All was well after bringing her back up. They sold the car to Camaro freaks.

You wouldn't add some TransGard red to the old girl's fluid?


Wow! 30oz low and no damage!!!

Not familure with Transguard.

 

[Kira]

My mistake. It's LubeGard (in the red bottle). It's a product said to be the A#1 product used by transmission rebuilders.

I felt it improve my troublesome Volvo transmission. I use the stuff as recommended (1 oz./qt. capacity).

Also, regarding the neighbor's Camaro T top, I never did drop the pan and change the filter as they wouldn't return any phone call which involved paying for supplies.

Small historical note:
They asked me to sell the car in April (trannie episode) then took the car back for Summer driving.
When I got the car back (to sell for them) it was >1 qt. low of oil.
I concluded they are dippy-doos.

 

[R18Civic]

Don't over or under fill. Just check the dipstick and ensure that the fluid is in the "safe" hash-marked area. Since it sits for most of the year I'd recommend upgrading to DEX VI. You could get away with changing it every 40-50k miles using that stuff despite how long it's been sitting.

I ended up over-filling my 4T65E just slightly and it caused all sorts of issues until I dropped the pan a second time and filled it to the proper level.

Slam shifts, whirring noise in low gear, fluid cavitation etc.

 

[Lubener]

Originally Posted By: Hemispheres
Don't over or under fill. Just check the dipstick and ensure that the fluid is in the "safe" hash-marked area. Since it sits for most of the year I'd recommend upgrading to DEX VI. You could get away with changing it every 40-50k miles using that stuff despite how long it's been sitting.

I ended up over-filling my 4T65E just slightly and it caused all sorts of issues until I dropped the pan a second time and filled it to the proper level.

Slam shifts, whirring noise in low gear, fluid cavitation etc.


Unless the fluid was visibly aeriated as seen on the dipstick, I doubt "slightly" overfilled caused your issues. Likely getting fresh fluid in there with your second pan drop, I would believe made your improvements. I have slightly overfilled those and never had a problem. Myself, I change fluid and filter on those GM units every 30k since they are not the best out there.