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jgrish
02/14/2006, 06:02 PM
Usually my overdrive kicks in at around 50mph, but its not kicking in till i drive it for about a half an hour. It never used to do that. I had my trans. fluid changed and then it started. I have no idea what it is. I took it back and they said it was some valve sticking so they put lucas trans stuff in it and its gotten a little better, it will go into OD every once in a while now but its still not going all the time. Any suggestions?

Thanks

Jeff

VehiGAZ
02/15/2006, 07:00 PM
The VX tranny doesn't have an overdrive gear. You are probably thinking of the lockup torque convertor engaging and disengaging (when it hooks up, your revs will fall, but only about 1/3 as much as a gear change would cause the revs to fall - 500 rpm vs. 1500 rpm).

From what I can tell, some VX torque convertors are very obvious about locking and unlocking, others not at all. It should lock up in 2nd, 3rd, and 4th gears. Are 2nd and 3rd still working correctly on yours? If not, have them check whatever could affect the performance of the torque convertor lockup mechanism. I'd guess that the wrong spec tranny fluid might cause that.

Good luck!

AREA 51
02/16/2006, 09:49 AM
We do have overdrive. Check the specs, 4th gear is 0.72:1. Make sure the shop properly filled the trans to specs : eng. running in park, fluid warm, not hot.

jgrish
02/17/2006, 02:16 AM
I talked to one of the mechanics and they said to fill it up and while it is in gear fill it up 3 more times after cycling through the gears and they did all of that. So i really have no idea whats going on.

VehiGAZ
02/17/2006, 05:22 AM
Area 51 - thanks for pointing that out. I had a misundertsanding of what an overdrive gear is, which was quickly corrected by the HowStuffWorks.com website. Plus, I figured if the top gear was an OD gear, it would say so, but I guess people like the idea of a 4-speed tranny without OD more than the idea of a 3-speed tranny with OD.

You learn something new every day...

AREA 51
02/17/2006, 07:53 AM
Check the level in gear? No way!. It even sounds dangerous.

If it's lucas trans conditioner and stop leak, that stuff is like stp for the trans. It's thick. I'd recommend you take it to a trans shop and have them check the pressure. It may be something is wearing out, like a solenoid , clutch, servo or band.

jgrish
02/21/2006, 02:41 PM
They figured out it was the transfer case lock-up valve. And its only $45 to get a new one. Thats a lot better than i had expected!!

Thanks for all the help!!

Tone
02/21/2006, 03:13 PM
Transfer case lockup valve sounds a little suspicious as I don't believe it has anything to do with tranny and overdrive. Keep us posted. I think your fluid flushed and the filter replaced since it just happened after a refill. And add an external tranny filter to keep the new fluid free of big particles.

VehiGAZ
02/22/2006, 08:20 AM
Tone, he's talking about the torque convertor lock-up mechanism, not the transfer case lock-up.

My first post suggested that the problem a failure of the torque convertor lock-up to engage, not a failure of 4th gear to engage. Sounds like that was indeed the problem, in which case the diagnosis is not suspicious at all - it's right on the money.

Good luck jgrish! Let us know what happens...

Tone
02/22/2006, 09:23 AM
Thanks - he posted transfer case lockup valve....

VehiGAZ
02/22/2006, 10:58 AM
Oh, I didn't notice that before. Hmm...

jgrish, now you're DEFINITELY going to have to tell us what they did and how it worked out!