Oil related problems with TH700.

[Hollowman]

Hi there! I just bought a Chevy van (I hope that's ok on this forum as well), with a 6,2 liter diesel and TH700. It's leaking a little bit of oil from the gearbox (I am not sure of the technical terms in English), and I filled it up with maybe 3 deciliters (about a soda can, if you are not familiar with this measure system). I had checked the oil level after driving enough to heat up the gearbox, and going through all the gears, and I think the oil I filled it up with was enough. After driving for a few hours more, I couldn't drive faster than 35 mph or so. The engine seemed fine, but it seemed like the rpm-level of the engine didn't match with the speed of the car anyway. It seems like the gearbox was slipping somehow. I didn't check the oil level after I came home unfortunately and I don't want to drive the van to heat it, but would it be a good idea to fill up some more oil? I will probably take it to a chevy mechanic this week to fix everything, but I don't want to tow it there if I can avoid it.

[Irish_Alley]

by gearbox you just mean the transmission? clean it all up with parts cleaner refill the transmission, then just let her idle and see where the leak is coming from. if no leak is found drive it a little to get the fluid moving. but remember the air flow will push the fluid back and all around.

[rich weyand]

You should be able to get it to leak if you are just sitting still with the brakes held on and the transmission in Drive.

Also, if you fill it with synthetic ATF it will leak easier, so you can spot it better.

[Hollowman]

Hey, thanks for the answers. I mean the transmission, but the problem isn't to find the leak, because I know where the leak is. The problem is that it was slipping in the transmission while I was driving (after a few hours), and I need to know if it's because it's too low on oil, and if I should fill it up with more (and how much?) before driving it to the local chevy repair guy.

[Captkaos]

How much is on the dipstick, don't over fill it...

[Irish_Alley]

[Hollowman]

When I tested it while the transmission was warmed up etc, it was in the part that said "fill up". After that I didn't measure again, because I didn't want to risk to drive it until it's hot without knowing if I should fill it up first anyway.  How much will it show "off" if I just test it without driving it first?

[Irish_Alley]

if its slipping, i dont think you have to worry about damaging it any more. i would add some lucas transmission slip fix after you fix the leak. and see where that gets you. ive seen transmissions be bone dry on the dip stick and slip then you top them off and if "fixes" the problem

[VileZambonie]

Check the fluid level with it running in park at operating temp. Make sure it's in the cross hatches on the indicator.

[Hollowman]

Cross hatches?

[81_Chevy]

Cross hatches?

The diagonal left and right etched lines on the dipstick.

[Hollowman]

Ah, yes, now I get it.  I will check it out this weekend. Thanks!

[VileZambonie]

see below