What the inside of a Gear Vendor looks like.

[AlanCasida]

In case anyone wants to know. This is a used unit I got some time ago and right before Dragweek it started having trouble, as in not disengaging. I was unable to get it to work right so I took it out and put in the one I had in my 65 Mustang project(also used) and went on my way. Today I decided to take it apart and see if I could find anything obvious wrong with it, which I could not.

[66FAIRLANE]

Interesting pics. I never want to see the inside of mine 

Maybe the issue was with the controller or speed sensor. Did you try swapping those before you pulled the unit?

[turbohunter]

Kinda curious about these things. I have never had one but am going to buy one for my truck.
My brother has one on his pickup and it just ate itself up. What he told me was that a fastener or two had let go inside an the unit was lunch. This is not a high powered truck, just a diesel with no turbo. It's a dog.
Then I read that the units can take a huge amount of hp. Such as Jays and other high powered stuff.
That doesn't figure with my brothers experience.
Figure your car is no slouch either as it runs low 12s.
BTW congratulations on your Drag week performance.
So my questions are first what do you think of these units?
Can someone with reasonable skills work on them?
You say you bought yours used. Do you recommend going that way?
Thanks for your time
Marc

[AlanCasida]

The problem is definitely internal. I cleaned the solenoid valve and then swapped it out first, no help. Since I shift mine manually the speed sensor didn't come into play. At any rate when I swapped units the problem went away. After looking at it closer what I think is going on is the pistons that engage/release the friction cone are getting cocked in the bores, not allowing it to disengage properly. It might need new piston seals or even the pistons replaced.
 Usually these units require virtually no maintenance and I would not hesitate to buy another used one. I think I paid around $1000 for this one and even if I have to send it to GV for repair(they want $950 to rebuild it) I will still be way ahead money wise.
 There's not much inside them but I am not sure if GV will sell just parts. They seem to be pretty protective of their product and don't want people working on them.
Oh yeah, on the last day of Dragweek I posted a personal best ET of 12.23@108mph. Not bad for a 4400lb tank! 

[66FAIRLANE]

Hi Marc

Can't speak for Alan but I love mine. Had it for 3 years and it hasn't missed a beat. I did a write up on the install if you are interested, it is here.

http://fepower.net/simplemachinesforum/index.php?topic=169.0

My Fairlane is nowhere near the horsepower levels of some of these guys (would probably run a high 12) and it does not hook on the street so it is not subject to those stresses. I bought new and went with GV as everything I read said that they were bulletproof and I figured I would never have to touch it. That reminds me, I should do a fluid change.

[Heo]

Looks exactly like a Laycook de normanville  that Volvo
used in the 60-70s
As i remember it. the issues they had was low oilpressure
due to worn pump. And worn friction material other than that
they were more or less trouble free

[machoneman]

Hone is back in business.

http://hone-o-drive.com/hone-o-drive/

http://www.stangerssite.com/honeodrive.html

Hone overdrive units were popular in the 70's even for light trucks and motor homes. Very cool is the fact that it bolts directly to a 9" Ford center and shifts instantly. Lighter, shorter and as strong as the Gear Vendors unit too. If I had to add a similar unit, I think I'd do the Hone for those reasons even though the GV is well tested and highly respected. JMO!   

[Drew Pojedinec]

Alan, I gave you a link to a guy that'll sell you parts and give advice on the FE forum.
His name is Glenn, he can be contacted at:  http://www.maximum--overdrive.com/products.html
Turbohunter:
If your brother's broke so easily, I'd make sure his speed sensor was disengaging it, the GV wasn't used in reverse, and he wasn't using it to compression brake the engine.
all of these are known to destroy one in short order.

If used properly, these are pretty troublefree units.

[turbohunter]

Turbohunter:
If your brother's broke so easily, I'd make sure his speed sensor was disengaging it, the GV wasn't used in reverse, and he wasn't using it to compression brake the engine.
all of these are known to destroy one in short order.

If used properly, these are pretty troublefree units.

Thanks Drew
I'll chat him up about it.

[Drew Pojedinec]

Ohh I found this old bookmark regarding Gear Vendors and rebuilding them:

http://www.oilburners.net/forums/showthread.php?40658-Gear-Vendor-OD-troubleshooting&highlight=gear+vendor

[66FAIRLANE]

Well. This thread shamed me into changing the fluid in mine. Jeez it was dark! Got me thinking it might be better off with Type F. I am currently using Dexron III. What are others using?

[jayb]

I'm using type F.  Rick Johnson at Gear Vendors warned me about using the GM synthetic fluid that is recommended in the directions; he says this is great for motorhomes and trucks, but not as good for a performance car.  He suggested any standard automatic transmission fluid, and I just used type F because that's what I've got.  Based on what Rick said, I don't think there would be anything wrong with using Dexron, though.

[Drew Pojedinec]

I use TypeF
It wears out faster than in a transmission, but it doesn't take much to fill it up so I don't mind changing it often.

I also have the large oil sump for mine.

[66FAIRLANE]

Thanks guys. I rang GV after my install and asked. I was advised to use Dexron. But based on the colour of this fluid I might change. I was really shocked at how brown it was. Looked like old engine oil.

[babybolt]

They were used in a AMC Pacer behind a Ford 3 speed toploader according to this Ebay ad:

http://www.ebay.com/itm/AMC-Pacer-Laycock-J-type-gear-vendors-3-speed-overdrive-Ford-4-speed-toploader-/191312288103?ssPageName=STRK%3AMESINDXX%3AIT&_trksid=p2047675.l2557&nma=true&si=OmHTNqoygHho6BiS%252FfjlRPGROqk%253D&orig_cvip=true&rt=nc