tranny slipping

[ccapehartusarmyINF.(ret)]

i have the 4l60e tranny in my tahoe
i started noticing it slipping very random and not very often
but recently its been slipping a bit more frequently its a minor slip and it only happens on take off no problems in any other gears
any input on what mite have started to fail? clutches?

 

[Yukongk]

Is the fluid level ok? I think you have to drive around to get it warm, then while idling, shift through each gear w the shifter and hold in each gear for a few seconds and then return to Park. Leave it idling and check your fluid. Should be in the crosshatches of "HOT" on the stick.
I would start there. My apologies if you already checked this.

 

[Mudfrog]

When I bought mine it would slip horribly once warm. Changed the fluid and filter and added some lucas and now it will only slip a little shifting into 3rd over 2,000 rpm. It's good enough to where I'm going to prolong buying a new tranny and I'm fine with that. When I dropped the pan it had so much clutch pad shavings that the filter was completely clogged.

 

[JBTJ]

Sounds like the filter and ALL of the fluid in the system needs to be replaced. Remember dropping the pan only accounts for about 1/4 of the fluid that the system holds.

 

[ezdaar]

instal vette servo and billet od servo

 

[ccapehartusarmyINF.(ret)]

okay ive only flushed a 4l60e tranny at school with a flush machinel, and the only tranny ive just changed out fluid in and replaced the filter was an E4OD tranny in an old f150 i had years ago is it roughly the same changing out fluid in the 4L60E

also if it does happen to be the clutches starting to wear out would installing a vette servo slow or accelerate that process in my autotrans class in school our intructor told us usually installing stuff like like shift kits and what not on a tranny with high miles may cause parts that might have held on for awhile to break much sooner

 

[TxDrewski]

okay ive only flushed a 4l60e tranny at school with a flush machinel, and the only tranny ive just changed out fluid in and replaced the filter was an E4OD tranny in an old f150 i had years ago is it roughly the same changing out fluid in the 4L60E

also if it does happen to be the clutches starting to wear out would installing a vette servo slow or accelerate that process in my autotrans class in school our intructor told us usually installing stuff like like shift kits and what not on a tranny with high miles may cause parts that might have held on for awhile to break much sooner

Roughly yes but remember just dropping the pan and changing the fluid and filter isnt a full "Flush". Best bet would be to by a filter and pan gasket as well as th efluid of your choosing (Im an AMSOIL or Royal Purple guy), taking it to a shop and having it fully flushed. I agree with your instructor on additions to an already weak/high mileage transmission. If your going to do tranny mods on a high mileage transmission, I would pull it and build it or have it built instead of putting performance parts on a transmission with worn parts. Im going to do a motor and tranny swap here soon, but I need my truck so i will acquire everything prior to pulling my stuff out. Not sure if you have that luxury, but if you dont, id definitely save the $$ from the mods to your current transmission adn have yours flushed and the filter changed and save up for a used one to rebuild, an already rebuilt one, or a performance built one. Just my .02 as always.

 

[ccapehartusarmyINF.(ret)]

well i was considering buying a used 4L60E and rebuilding it myself
while the one in my tahoe now is still good

 

[JBTJ]

Taking it to a shop is the worst thing to do. The flush machines they use are ok IF the transmission has been flushed on a regular basis. The problem becomes apparent when you have a transmission that has not had the service done regularly and the process removes the particulate matter from the small nooks and crannies and redeposit's them in other areas due to the back flushing procedure and can cause blockage and burn up the transmission.

The best way and safest is to simply replace the fluid using the transmissions pump. Like mentioned, just simply dropping the pan and replacing the filter in not good enough. The pan hold about 5 quarts, but there is about 11 more quarts in the torque converter. So it is pointless to only change 1/3rd of the fluid in the system.

This method can be done by removing the cooler line at the top of the radiator on the passenger side. Then connect a brass barb fitting to the radiator that will accommodate a 3/8th's rubber hose about 3 feet long. Get a milk jug marked off in quart increments. Take the other end of the rubber hose and put it in the milk jug and have a buddy start the engine. This will begin to pump the old fluid out into the milk jug. Allow it to fill up to the 4 quart mark line. Turn off motor and pour in 4 quarts of fresh fluid into the dipstick tube. Simply repeat the process until you get fresh clean coming out into the milk jug.

If you really want to make this easy, add on an external filter. This way you will no longer need to crawl under the truck and change the internal filter and make a mess doing so. You can simply stand up and change the filter in about 20 seconds. This method will also aid in exchanging out all the fluid in the system by removing the input line at the filter adapter and sticking that hose in your milk jug. BTW I do this process every year.

Though I now use a hydraulic filter from NAPA p/n 1269 that is capable of filtering down to 10 microns that is not shown in this pic.

 

[Big Buttons]

A corvette servo and billet od servo holds the band inside the tranny to firm up the shifts a little bit. Lots of guys have installed this and it stopped light slipping.