Chevy & GMC Vans

My 2000 AWD shifts really hard into second under light to regular acceleration but it shifts normally under harder acceleration and it holds firm in every gear all the time. I've tested it in tow/haul mode and it acts the same way. The van has about 144,000 miles on it and the fluid was/is a little more brown than I'd like. The day i brought it home i changed the filter and refilled it with mobil 1 synthetic ATF. You could tell the pan hadn't been dropped in a long time, possibly never and it didn't have any metal in it, just the thin layer of black gunk that coats the bottom of the pan and there wasn't anything in the filter.

I don't know transmissions very well and don't know how to go about diagnosing this problem.
Any ideas?

These 4L60E's shift pretty hard. It's normal. Nothing to worry about. Nothing in the pan is a plus.

Skips right. The one in my Jimmy shifts hard also,,in fact, it shifts as hard as the 700r in my van after all the shift updates.

It shifts REALLY hard. It's hard enough that if i don't do something about it it will eventually break something in the driveline.
Sometime after i started the topic i noticed the sticky in this section that sounds like the exact same problem I'm having.
viewtopic.php?f=5&t=4494
Guess i should have looked around a bit before posting

The topic mentions many factory valve body changes in the 2000 run. I can probably come across a 01+ valve body somewhere pretty cheap. What about swapping in a newer valve body?

Does it tend to do it more when hot? Mine used to do it when it got hot. A large trans cooler and synthetic will help. I know you currently have synthetic but it is due for a change sounds like. I would think a newer VB would fit with no issues.

LiftedAWDAstro wrote:Does it tend to do it more when hot? Mine used to do it when it got hot. A large trans cooler and synthetic will help. I know you currently have synthetic but it is due for a change sounds like. I would think a newer VB would fit with no issues.

After reading the sticky last night i payed a lot more attention to see if the symptoms change as the transmission heats up.

Today i drove 15 miles to the folks house (majority on the freeway), it sat for about six hours, then drove it back home.
each way it worked exactly as it should at first then slowly started shifting harder, even at it's worst today i only noticed because i was specifically paying attention.

If you install a transgo shift kit that problem will most likely go away. I have fixed several with the same problem. It takes me 3 to 4 hours to get the job done in my driveway. With a lift I could save a half hour to an hour. Parts should be less than 60 plus ATF.

They are not very hard to install but you have to follow the instructions very carefully and they can be a bit tedious. A first timer may take up to 6 hours to get the job done. I always use the cork gasket at the pan and install new valve body gaskets. Carefully clean the old gaskets off the valve body and separator plate.

Would this be the right one?
http://www.transgo.com/gmsk/4L60E-4L65E.html

Yes, that's the one. But... if your trans is a rebuilt by Goodwrench trans the new transgo iso-converter valve won't fit but you can buy a new one from transgo. If you send me a private message with your mailing address I will send a used slightly greasy copy of the installation sheets that go with the shift kit so you can see what you are getting into before you start or buy the kit.

There are a few other things you may need to know before you start and the instruction sheet is a good place to learn.

Tools you will need are:
13 mm socket and extensions.
10mm socket and speed wrench and ratchet
8mm socket
good snap ring pliers to remove and reinstall the pressure regulator valve in the pump.
small cordless drill and .093, .070, .075 drill bits.
small pics and screwdriver
1/4" drive inch/pound torque wrench
big drain pan
clean shop floor so you can find the small parts that get dropped
vaseline petroleum jelly or equivalent

Good luck

I installed the Transgo shift kit yesterday and got my auxiliary cooler all plumbed up.
It still shifts kind of hard into second, i would describe it somewhere between firm and really firm but it shifts at the proper RPM and isn't brutal like it was.




Added drain plug.



My separator plate was worn pretty bad and one of the check balls was lodged in the plate. Got a new Transgo plate.



One of my valves had a broken spring behind it but i can't remember which one.



Thanks for the instructions my4ateyour8, they really gave me a good idea of what i was in for.

Nice job. The shift kit will make it shift quicker and firmer but hopefully not slam into the next gear. The addition of the trans cooler will provide the most beneficial gain.

I too purchased a drain plug install kit, but was talked out of it. The "tranny guy" swore up and down it would never seal.

Please tell me if yours is successful.

This is the one i used: http://www.summitracing.com/parts/SUM-G1380/
I would rather have bought a new 1/2"-20 drain plug from a local auto parts house and welded a nut on the inside of the pan but this was just easier and it's the same size hole, so if for some reason i don't like it i can always go back and do the weld job on it. Don't know why that guy would think an added plug would be more likely to leak than any other plug in anything else. I really hate dropping a pan that doesn't have a drain plug.

Its to the Tranny man's advantage if you seldom, if ever, change your fluid.

astrozam wrote:Its to the Tranny man's advantage if you seldom, if ever, change your fluid.

always the skeptic …good point.

I bought mine from bulkpart.com. I'll be sure to add it the next time I drop the pan. Again, mention if yous starts to leak, thanks.