Anyone using Gear Vendors Over/Under Unit?

[Possmguts]

Anyone here using the Gear Vendors Over/Under unit on a TH350 or TH400? You like? Pros and cons? Im reading it makes you 3 speed act like a 6 speed high/low.

[Coley]

A buddy of mine went the Gearvendors route in his '68 Charger RT/440. He seems to like it....makes it interesting.
It hasn't given him any real problems at this point...and his (440) engine is making some nice power through it.
The main advantage is the top highway gear....the other gears don't make too much difference to any regular driving (mostly novelty shifts)....so consider it for the overdrive (top gear) advantage only.
That said, they are not giving it away by any means from a price point. I would simply look for a Heavy duty 700 Series or a 4L60....probably quite a bit cheaper and simpler swap out.
all good
Coley

[Vintage Windmills]

Originally Posted by Coley

The main advantage is the top highway gear....the other gears don't make too much difference to any regular driving (mostly novelty shifts)....so consider it for the overdrive (top gear) advantage only.

For the granny 4 spds (really 3 spds) wide ratios-the gearvendors benefit of filling in the gaps is probably the biggest advantage

[Lemield]

Originally Posted by Possmguts

Anyone here using the Gear Vendors Over/Under unit on a TH350 or TH400? You like? Pros and cons? Im reading it makes you 3 speed act like a 6 speed high/low.

I had one on my 1970 CST that I sold a couple of years ago. It was fun. Pretty pricey though. I liked it. The new owner likes it too. It was on a TH350 and it was easy to install.

[HSRACER]

I have two of them both behind my 650 hp blower motors. that is the main reason for both. the gear vendors will handle up to 1200 hp in their stock configuration and can be modified to hold 2000 hp. I agree with others here that they are pretty expensive but the really work well for high HP engines. one is 12 years old and the other is 9 years old and both have seen the rath of these blower motors with out a hint of problems.

my other vehicles with stock engines all have 700 r or 4l60 in them. the only reason I would use a gear vendor is hp over 500.

[Possmguts]

Yeah that do cost a lot but I like how it splits the gears keeping you in the power making RPM range with no over revving or lugging. That and the OD. Still mowing over options....

[Daaaanz67]

I rode in a 72 GMC once that was powered by the GM 300hp crate motor. We were pulling a 37 chevy on a car trailer through the mountains. I was real impressed how effortless the truck was working when the gears were split.

[Fitz]

Originally Posted by Possmguts

Anyone here using the Gear Vendors Over/Under unit on a TH350 or TH400? You like? Pros and cons? Im reading it makes you 3 speed act like a 6 speed high/low.

I backed up a built TH400 with a Gear Vendors unit. Splitting gears is easy with this overdrive BUT my TH400 was built by JWRacing and it has no automatic shift. The auto shift valve was replaced with a manual unit so I never have to dance between the gear Vendors unit and the trans when running up from a standing start. And, yes, it does make the 3 speed act like a six. I run a 4:10 rear but in third over rpm's are 2200 at 70 mph!

The trans/overdrive combo is long (on mine the yoke is just 8 inches in front of the trailing arm crossmember) so you will need a MUCH shorter driveshaft. It will handle more torque than a 700R4 so for me it was a much better choice.

[Possmguts]

Originally Posted by Fitz

I backed up a built TH400 with a Gear Vendors unit. Splitting gears is easy with this overdrive BUT my TH400 was built by JWRacing and it has no automatic shift. The auto shift valve was replaced with a manual unit so I never have to dance between the gear Vendors unit and the trans when running up from a standing start. And, yes, it does make the 3 speed act like a six. I run a 4:10 rear but in third over rpm's are 2200 at 70 mph!

The trans/overdrive combo is long (on mine the yoke is just 8 inches in front of the trailing arm crossmember) so you will need a MUCH shorter driveshaft. It will handle more torque than a 700R4 so for me it was a much better choice.

In your pic it looks like the trans mount was moved back... is it?

[toolboxchev]

Originally Posted by Fitz

I backed up a built TH400 with a Gear Vendors unit. Splitting gears is easy with this overdrive BUT my TH400 was built by JWRacing and it has no automatic shift. The auto shift valve was replaced with a manual unit so I never have to dance between the gear Vendors unit and the trans when running up from a standing start. And, yes, it does make the 3 speed act like a six. I run a 4:10 rear but in third over rpm's are 2200 at 70 mph!

The trans/overdrive combo is long (on mine the yoke is just 8 inches in front of the trailing arm crossmember) so you will need a MUCH shorter driveshaft. It will handle more torque than a 700R4 so for me it was a much better choice.

That is Very Purdy!

[cleszkie]

I've had my Gear Vendors unit for several years now in my K5 Blazer. Had it hanging off the back of my NP205 transfer case when I ran a TH350 auto, and now have it hanging off the back of the same NP205, but now I run an SM465 4 speed. Probably the best upgrade I've ever made, and I've made a lot of nice performance upgrades As others have said, it is a very strong unit. Change the oil/ATF every now and then and it will last a lifetime. As others have said, it provides nice overdrive for cruising down the freeway. But I find that I use it more to help me tow heavy loads over the mountain passes. With my manual tranny, it allows me to split every forward gear to keep the engine in the power band. I have 1st, 1st overdrive, 2nd, 2nd overdrive, 3rd, 3rd overdrive, 4th, and 4th overdrive. When I am pulling a loaded car hauler up the Cajon Pass in SoCal, 3rd overdrive is my sweets spot.

I found the Gear Vendors complete with all wiring, switches, and brain in an '86 2 wheel drive Suburban behind a TH400 at an Ecology Pick a Part several years ago when the cash for clunkers incentive was going on in California. Everyone was cashing in their older rides. Got it for $100.

[HO455]

I have one for my Javelin and the only shortcoming with it is no lock up converter with a T400. That would be the ultimate set up.

[mcmlxix]

Originally Posted by cleszkie

I found the Gear Vendors complete with all wiring, switches, and brain in an '86 2 wheel drive Suburban behind a TH400 at an Ecology Pick a Part several years ago when the cash for clunkers incentive was going on in California. Everyone was cashing in their older rides. Got it for $100.

... you robbed them blind ....

I wouldn't have tried to squeeze it in a lifted Blazer for fear of driveline angle... but a low long wheel base truck...

[cleszkie]

Originally Posted by mcmlxix

... you robbed them blind ....

I wouldn't have tried to squeeze it in a lifted Blazer for fear of driveline angle... but a low long wheel base truck...

Everyone seems to think that. But it actually fits really well with a perfect driveline angle. I had to source out a 300 series slip yoke from a Cadillac application, which combines the slip yoke and CV joint into the shortest known factory setup. I then cut the spring perches on my rear axle and rotated the axle pinion to point right at the GV output. No vibration, and plenty of play in the slip yoke for axle movement. Been this way for 7 years now. Attached are some old pics during the install.

[chewychevy67]

Ttt. I am thinking about putting a gv in my swb and wanted to know if the cross member needs to be moved as well. My bad just realized Fitz account was suspended.

[Mick Je]

Have one in my motorhome absolutely awesome especially for towing. One of these days I want to put one in my 70. Sure they are pricey but definitely worth it in the long run.

[Lemield]

Originally Posted by chewychevy67

Ttt. I am thinking about putting a gv in my swb and wanted to know if the cross member needs to be moved as well. My bad just realized Fitz account was suspended.

I did not have to move the crossmember at all. I had a short shaft TH350 and the GV adapter just bolted on to the back of the transmission. I did have a new shorter driveshaft made. Very easy install as I recall.

[James the III]

Only ones that think they are pricey are those that have not priced out a built 2004r or 7004r /4l60 /4l65 and a good converter and in the electric controlled trans the shift controllers..
You will find the 2200-2300 is not pricey when you find a built g.m. o/d automatic will run you 3500-4500 ...
Most that have a 2000-2500.oo built 7004r don't have them last for long..
Many get by with them, but then again never really use the power the engine has either..
A th200 can live behind a 500 hp engine if you never hammer it..

[special-K]

I was going to say the same type of thing. A Gear Vendors unit isn't expensive at all when you figure they all outlast even the best O/D automatic. GVs get taken from one vehicle and moved to the next when their host vehicle gives up the ghost. And, if you ned brute strength, they are the way to go. It's a gear box, nothing complex.

I had one in the diesel '84 K/30 I had with Banks Sidewinder. I absolutely loved it behind that TH400. I plan to one day have one in my '67 SWB 327/M22/3.42s for an ultimate hot travelin'/haulin' truck rod.

[jeffahart]

Originally Posted by special-K

I was going to say the same type of thing. A Gear Vendors unit isn't expensive at all when you figure they all outlast even the best O/D automatic. GVs get taken from one vehicle and moved to the next when their host vehicle gives up the ghost. And, if you ned brute strength, they are the way to go. It's a gear box, nothing complex.

I had one in the diesel '84 K/30 I had with Banks Sidewinder. I absolutely loved it behind that TH400. I plan to one day have one in my '67 SWB 327/M22/3.42s for an ultimate hot travelin'/haulin' truck rod.

I've got my eye out for one. I may just end up buying new. But to the point above. If you keep your original driveshaft, you can pull the GV, hookup old shaft and sell the GV if you decide to get rid of your truck. Plus I cannot see the trouble of retrofitting a NV with an OD when you can get a GV. GV seems like a logical choice to me. Also, I'm 4x4 so I would be on the 205 transfer(a side note). I know I really didn't add anything to the conversation here, but I am very interested in the GV threads.

[Tom Vogel]

A Great piece of equipment. Top Notch reliable.

[Greg58]

I have a 2wd, 1987 Sub. 2500, 454, t-400 with 4:10 rear gears. The PO installed a US Gear under/overdrive unit, and I love it.
I agree that you don't switch up and down with each shift, (not practical) but it is useful when running empty to reduce the engine rpm. It takes the 4:10 and reduces it to about 3:10.
I have towed many times in the lower numerical range, and the truck responds well with plenty of power. If you get into hills, lower gearing is just a click away.
As far as fuel economy, there is no such thing with a 454/t-400 combo, but I figure that keeping the RPMs down at highway speeds is good for my engine.
Greg