Gear Vendors Overdrive

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Has anyone use a Gear Vendors Overdrive with a C6? If so what do you like or dislike about it?
A friend has been running a Gear Vendors on a 1970 428scj c6 for the last two years. I'll call him for feedback and post results.
 
OK 'Irish here is feedback from friend with 1970 428scj, 3:89 gears, c6 Stang w/Gear Vendors; He loves it...strong with nice shifts, a 500+ hp car. Install was straight forward with no issues. He lives in Pittsburgh, PA me up in Erie. He makes the 100 mile trip (200 round trip) couple times a summer, no problems. With the overdrive the 3.89s are sweet at 70mph. He did not like the "high beam foot switch" shifter and converted it to a shifter handle button. He also said a trip to the muffler shop is mandatory if you're running an x or h pipe.
Hope this helps.
Chris
 
I wish I had known about Gear Vendors before I did the AOD swap. All I've read on them has been positive. The AOD is fine but it's not a C6.

I'm moving on to a 5-speed.
I was really torn re: doing the AOD, or building the C4 to be bulletproof (and maybe getting a GearVendor overdrive). In the end I would have had to rebuild the C4 (it began to slip badly in the 1-2 upshift at Wide Open Throttle), so rather than go through a C4 super-build, or swapping a C6 or even FMX and adding GearVendor, I (also) opted to do an AOD swap. I have no regrets as the AOD is performing nicely. I did increase the Throttle Valve pressure from the 30-35 PSI factory value to 39 PSI, just to increase the road speed for the 1-2 and 2-3 shifts (it made the shifts a bit firmer also). I know of a few other folks that also did the AOD swap. and everyone seems to be plenty pleased. But, if I had much more than the 360 HP our moderate StreetStrip 351W (not C) puts out I may have also opted to do some GearVendor inclusion as well, with a built FMX. But, I am fine how the AOD project turned out. I went far easier than I had anticipated, and the Throttle Valve setting, although cumbersome, was not all that tough to do. I have some documents with a parts list, vendors used, and videos of the entire AOD swap process. The videos include one clip where I splice the old C4 NeutralSafety/BackUp Light Switch (NSS/BUL) harness to work with an AOD NSS/BUL light harness. There are also several Throttle Valve Adjustment videos. The various video links and descriptions are in the relevant file attached to this post, for anyone interested.
 

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OK 'Irish here is feedback from friend with 1970 428scj, 3:89 gears, c6 Stang w/Gear Vendors; He loves it...strong with nice shifts, a 500+ hp car. Install was straight forward with no issues. He lives in Pittsburgh, PA me up in Erie. He makes the 100 mile trip (200 round trip) couple times a summer, no problems. With the overdrive the 3.89s are sweet at 70mph. He did not like the "high beam foot switch" shifter and converted it to a shifter handle button. He also said a trip to the muffler shop is mandatory if you're running an x or h pipe.
Hope this helps.
Chris
Thanks for the info! Been knocking around the idea since I'm going to be using 3.70 gears and have to drive on highways as well get to some places.
 
I was really torn re: doing the AOD, or building the C4 to be bulletproof (and maybe getting a GearVendor overdrive). In the end I would have had to rebuild the C4 (it began to slip badly in the 1-2 upshift at Wide Open Throttle), so rather than go through a C4 super-build, or swapping a C6 or even FMX and adding GearVendor, I (also) opted to do an AOD swap. I have no regrets as the AOD is performing nicely. I did increase the Throttle Valve pressure from the 30-35 PSI factory value to 39 PSI, just to increase the road speed for the 1-2 and 2-3 shifts (it made the shifts a bit firmer also). I know of a few other folks that also did the AOD swap. and everyone seems to be plenty pleased. But, if I had much more than the 360 HP our moderate StreetStrip 351W (not C) puts out I may have also opted to do some GearVendor inclusion as well, with a built FMX. But, I am fine how the AOD project turned out. I went far easier than I had anticipated, and the Throttle Valve setting, although cumbersome, was not all that tough to do. I have some documents with a parts list, vendors used, and videos of the entire AOD swap process. The videos include one clip where I splice the old C4 NeutralSafety/BackUp Light Switch (NSS/BUL) harness to work with an AOD NSS/BUL light harness. There are also several Throttle Valve Adjustment videos. The various video links and descriptions are in the relevant file attached to this post, for anyone interested.
Thanks for the input. Interesting alternative for sure. But being a paleo-centric kind of guy I believe I'll stick with the C6. Thanks for taking the time to share.
 
I had a Gear Vendor in my 88 F250 460 C6 4x4 for years. Towed a 33 foot 5th wheel toy hauler. A case of picking up the trailer from the dealer and putting water, gas , dune buggy in it to find the truck won't pull it. The GV maid it possible to tow the trailer with a 460. My fuel mileage empty went from 8 to 11 mpg. Towing 4 to 7 mpg. I did cam, headers, cat delete and flowmaster exhaust first with marginal gain. Should have done the GV before the cam swap. GV hands down was the best bang for the buck highly recommend it .

With that being said my plan was to go the C6 GV route in my Mach 1. When I looked at the numbers for GV and C6 build I was close to Tremec money. I ended up going with Tremec for the fun of the 3rd peddle.
 
Thanks for the input. Interesting alternative for sure. But being a paleo-centric kind of guy I believe I'll stick with the C6. Thanks for taking the time to share.
Despite their reputation for having a fairly high level of parasitic loss., those C6 units are damn near bulletproof. Very strong units, and with a lot of build potential. If we had a C6 behind our 351 in the 73 Mach I would haver done a GearVendors swap vs swapping in an AOD. I am very pleased with the AOD, but the durability of the C6 is legendary. Alas, as I remember, the C6 will not bolt up to a 351W or 302 engine. No matter, I am truly more than satisfied with the AOD. Having an OverDrive final tranny gear is so cool... Oh, yeah, and practical...
 
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Despite their reputation for having a fairly high level of parasitic loss., those C6 units are damn near bulletproof. Very strong units, and with a lot of build potential. If we had a C6 behind our 351 in the 73 Mach I would haver done a GearVendors swap vs swapping in an AOD. I am very pleased with the AOD, but the durability of the C6 is legendary. Alas, as I remember, the C6 will not bolt up to a 351W or 302 engine,No matter, I m truly ore than satisfied with the AOL. Having an OverDrive final tranny gear is so cool... Oh, yeah, and practical...
You just have to find a small block pattern C6.

I have one I bought, but never ran as I decided to go 4 spd on the third try of my build.

edit:

here you go.

https://www.summitracing.com/parts/tci-411400/make/ford
 
You just have to find a small block pattern C6.

I have one I bought, but never ran as I decided to go 4 spd on the third try of my build.

edit:

here you go.

https://www.summitracing.com/parts/tci-411400/make/ford
You know something? It is certainly true about being able to learn something new every day, if you just look for it. In the case of this thread, I knew the "regular" C6 would not bolt to a small block engine - or I may have known it and totally forgot about that. But, until today I never knew there was a small block C6, but it makes sense that they are out there, for trucks using a 302 or 351W engine if no other reason. I think had I know of the small block C6 I might have gotten one of those with a Gear Vendors OD unit, despite the added cost in comparison to getting the AOD tranny, just to get the strength out of the C6 and GV units if nothing else. I have not heard that the AODs are wimps when it comes to how much horsepower they can handle, but definitely like the C4 they haver some limits. What I found re: how much power those can handle includes:

"C4 trannys are rated at 450 ft/ lbs. AOD rated at 506 ft/lbs. In race ready form either can handle up to 800ft/lbs and 1200 HP"

The 351W (not C) in our 73 Mach 1 clocked in at 360 HP on a dyno run after the engine was rebuilt, a moderately powerful street/strip engine running with only 9.5:1 forged aluminum pistons in order to handle the lower octane ethanol free gasoline in our area. The HP rating was told to me by the prior owner, and he did not tell me the torque level. Bu, I did do a chassis dyno run on the Mach 1 about 3 years ago. in comparing the chassis HP to the crankshaft HP, then applying the ratio to the torque level, the built 351W would have about 400 LbFt on a fairly flat and wide band of both HP and torque. If that is close to accurate, it is easy to see why the C4 began to slip so badly after a bevy of Wide Open Throttle 1-2 upshift, where there was enough torque to cause the rear tires to fairly significantly break traction at speed. The AOD is rated for a little more torque than the C4, but you can believe it when I say I do not plan to push things to verify it being more durable than a C4.

That said, if the AOD does begin to slip, now knowing there is a small block C6, I will likely pop in a C6 and a Gear Vendor OD unit, just to be able to handle the power of even the mid-level street/strip build on the 351W. An alternative would be to get an FMX and drop it in with a GearVendor OD, as those FMX tranny units are definitely tough. But, they are very heavy (cast iron case) and I do not see a lot of vendors offering as wide a choice of high performance parts for the FMX, which is a shame as the FMX is really a well designed tranny.
 
You know something? It is certainly true about being able to learn something new every day, if you just look for it. In the case of this thread, I knew the "regular" C6 would not bolt to a small block engine - or I may have known it and totally forgot about that. But, until today I never knew there was a small block C6, but it makes sense that they are out there, for trucks using a 302 or 351W engine if no other reason. I think had I know of the small block C6 I might have gotten one of those with a Gear Vendors OD unit, despite the added cost in comparison to getting the AOD tranny, just to get the strength out of the C6 and GV units if nothing else. I have not heard that the AODs are wimps when it comes to how much horsepower they can handle, but definitely like the C4 they haver some limits. What I found re: how much power those can handle includes:

"C4 trannys are rated at 450 ft/ lbs. AOD rated at 506 ft/lbs. In race ready form either can handle up to 800ft/lbs and 1200 HP"

The 351W (not C) in our 73 Mach 1 clocked in at 360 HP on a dyno run after the engine was rebuilt, a moderately powerful street/strip engine running with only 9.5:1 forged aluminum pistons in order to handle the lower octane ethanol free gasoline in our area. The HP rating was told to me by the prior owner, and he did not tell me the torque level. Bu, I did do a chassis dyno run on the Mach 1 about 3 years ago. in comparing the chassis HP to the crankshaft HP, then applying the ratio to the torque level, the built 351W would have about 400 LbFt on a fairly flat and wide band of both HP and torque. If that is close to accurate, it is easy to see why the C4 began to slip so badly after a bevy of Wide Open Throttle 1-2 upshift, where there was enough torque to cause the rear tires to fairly significantly break traction at speed. The AOD is rated for a little more torque than the C4, but you can believe it when I say I do not plan to push things to verify it being more durable than a C4.

That said, if the AOD does begin to slip, now knowing there is a small block C6, I will likely pop in a C6 and a Gear Vendor OD unit, just to be able to handle the power of even the mid-level street/strip build on the 351W. An alternative would be to get an FMX and drop it in with a GearVendor OD, as those FMX tranny units are definitely tough. But, they are very heavy (cast iron case) and I do not see a lot of vendors offering as wide a choice of high performance parts for the FMX, which is a shame as the FMX is really a well designed tranny.
Glad I could help. Good luck in your project
 
Is it for sale?
Yes.

Haven’t listed it yet.

Bolted in the car so it could be moved from the shop.

Never has had fluid in it.

Has alternate first gear for better launch. Still 1:1 third so you can still drive on highway

Have a converter, too. It is in it now in storage. Same deal. Never had fluid in it.
 
Two alternatives:
1. In my 1967 GTA I put a non-electronic AOD, with the downshift lever. Great on the highway. Quiet, but not a hipo unit.
2. I upgraded a 4R75W to take 500 hp & torque, and even with 4:30 gears, it was great on the highway. May have cost less than the Gear Vendors.
 
Two alternatives:
1. In my 1967 GTA I put a non-electronic AOD, with the downshift lever. Great on the highway. Quiet, but not a hipo unit.
2. I upgraded a 4R75W to take 500 hp & torque, and even with 4:30 gears, it was great on the highway. May have cost less than the Gear Vendors.
I am curious. What electronic controller did you choose? Can you adjust shift points for the 1-2 and 2-3 upshifts electronically? Can you adjust line pressure and/or overall firmness in shifting? I am fine with our AOD upshift points, and firmness, now tha I am running at 39 PSI Throttle Valve Pressure. But it would be fun to be able to tinker with those pressures without having to break out the oil pressure gauge each time I want to play,
 
I am curious. What electronic controller did you choose? Can you adjust shift points for the 1-2 and 2-3 upshifts electronically? Can you adjust line pressure and/or overall firmness in shifting? I am fine with our AOD upshift points, and firmness, now tha I am running at 39 PSI Throttle Valve Pressure. But it would be fun to be able to tinker with those pressures without having to break out the oil pressure gauge each time I want to play,
Alt 2, the factory electronic controls (2003 Mercury Marauder) were adequate for Mo's Speed Shop in Atlanta to tune the engine and tranny to cooperate at 6400 RPM, including shift point selection. I can't answer about throttle valve pressure.
 
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