No Overdrive
#2
6th Gear
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Originally Posted by Black_Vette
86 4+3 Speed Vette's Overdrives wont come on anymore. Any ideas as to where or what I should look into.
On a positive note, the overdrive unit is working flawlessly. Removing the transmission is not just a job, it is an adventure! Not for the faint of hart.
#3
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If the overdrive unit is very low on transmission fluid, there's a lockout that won't let it engage. I'd recommend that you check the fluid level first.
Also, I've been told that if the O/D fluid is black in color, that's an indication that you have a leaking seal between the tranny and the O/D. (don't know if that's true or not)
Also, I've been told that if the O/D fluid is black in color, that's an indication that you have a leaking seal between the tranny and the O/D. (don't know if that's true or not)
Last edited by BamaVette87; 05-12-2005 at 09:15 PM.
#6
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I have this "thing" about folks who check my fluid levels. After having been burned once a long time ago, I started checking after them. And I've found on several occasions that I'm glad I did! If you can believe it, some folks actually tell untruths about checking those things!
(Sometimes they also top off fluids with the wrong type!)
(Sometimes they also top off fluids with the wrong type!)
#7
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Originally Posted by frank j. moran
is the light working on the dash???
Does it not only come on when your car is in one of the overdrive gears or should it be on all the time when the overdrive in engaged.
#8
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Doug Nash Overdrive Unit
OK - let me set the record straight. I had overdrive failure. I have completely rebuilt my overdrive unit and have researched it. For more information please see 4 speeds.com.
1) the reverse housing gasket between the transmission and the reverse housing actually lets fluid past into the reverse housing cavity. If that gasket is bad you will not have a problem with the overdrive, nor will you have a problem if the gasket between the two units is bad. The fluid can mix if the overdrive input sun gear seal goes bad. That will cause problems.
2) Black fluid is not from gear oil and ATF mixing. It is from ground up metal. Black fluid in the overdrive is an indication that the planetary gear carrier bearing is going out. Check out 4 speeds.com.
3) If your overdrive unit has not been redone by someone that knows what they're doing - namely SK Speed, plan on your overdrive unit failing at some point. When I bought my car at 48,000 miles the fluid was black. It took about 30,000 miles for it to get bad enough for the overdrive to begin making noise. Bad deal. I spent over $900 just in transmission parts and did the work myself. That didn't include the clutch and a bunch of other stuff.
Hope this helps.
1) the reverse housing gasket between the transmission and the reverse housing actually lets fluid past into the reverse housing cavity. If that gasket is bad you will not have a problem with the overdrive, nor will you have a problem if the gasket between the two units is bad. The fluid can mix if the overdrive input sun gear seal goes bad. That will cause problems.
2) Black fluid is not from gear oil and ATF mixing. It is from ground up metal. Black fluid in the overdrive is an indication that the planetary gear carrier bearing is going out. Check out 4 speeds.com.
3) If your overdrive unit has not been redone by someone that knows what they're doing - namely SK Speed, plan on your overdrive unit failing at some point. When I bought my car at 48,000 miles the fluid was black. It took about 30,000 miles for it to get bad enough for the overdrive to begin making noise. Bad deal. I spent over $900 just in transmission parts and did the work myself. That didn't include the clutch and a bunch of other stuff.
Hope this helps.
#9
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#10
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I uploaded some info for you. Its right out of the bible
http://members.shaw.ca/agent86/Overdrive-manual.pdf
http://members.shaw.ca/agent86/Overdrive-manual.pdf
#11
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Thanks for all the info on the Overdrive question I posted, I found the problem, it was a defective Overdrive relay located on the firewall.
Problem is now solved
Thanks again
Problem is now solved
Thanks again
#12
Team Owner
Nice work. That relay is a bugger. Take a 2nd look at the wiring and see if any of the wires are exposed. The insulation on that one tends to shrink over time.