Hello,

I am interested in information from those of you familiar with GEAR VENDORS OVERDRIVES

Do you have a problem ?

Do you have a vibration ?

What type of car installed in ?

What have you tried to fix the problem ?

Did you get the problem fixed ?

How did you fix it ?

Tips , comments , suggestions

Have you called them to diagnos the problem first? They might have a simple solution for you.

We just had to remove the GV "brain box" in my bro's 69 4speed Charger (518 Hemi), since it would pop out of OD with no warning. Dave at GV was helpful, but said it could be a RF issue or a voltage drop issue. Seems that if voltage goes below 12.7, it'll turn itself off & he said Optima batteries & stroker motors seem to draw more starting voltage, making that a problem. We have 2 Optimas in the trunk & one had the positive terminal come loose, which caused the problem...so we thought. After it happened again, we bypassed the GV brainbox & it seems to have fixed it...almost. But also seems a custom made shifter button (micro switch) that controls both the GV and the line lock may be causing it to go into OD on its own. SO, the next fix is to disconnect the line lock from the micro switch & switch to its own on/off switch in the ashtray.

Same guy that just posted the same thread on the HAMB site without an introduction.

I would expect most vibration problems to stem from having to shorten the drive shaft. It can cause drive line angle issues or the shaft itself can be the problem if it wasn't modified straight and true.

If I was doing one I would use a short shaft 727 from a 4x4 with divorced transfer case or a motorhome trans and use the "shorty" GV.


Kevin

I've done both the the auto 727 and 4spd 883 Mopar Gear Vendors OD's running "stock" type batteries, new charging systems, new wiring harnesses, etc, etc, what a stroker motor has to do with the issues doesn't jive, sounds like a line of BS from GV, both gear vendor OD in separate cars (one with a stroker, and one with a stock 440) would experience the "drop out" of the OD, not fun with 4:10's and running in triple digit speeds, was a very unreliable system IMHO...we did the usual shuffle with GV replacing modules, harness, switches, etc,...put the problem always persisted

They are of no help

if getting power direct from the battery should not have a LOW voltage problem.....over voltage could be handled with the correct value of zener diode

Micro switch problem can be caused by normal vibration of the car since the contacts in a micro switch are very light weight and very close together

I hope you are using a relay with a micro switch. That shift solenoid draws a lot of juice and I'm pretty sure it's more than a micro can carry.

Kevin

No problems in my '89 GMC Dually, 454/T400. Been in there since 1994. I used the switches provided by GV: foot/dimmer-switch and the rocker switch, which fit into a knock-out accessory provision on the dash.

My bro's car has 4:10's & was always able to get it into neutral before it revved too high. Wish he could've gotten a Passion 855, but the wait was too long. I'm certain we've got the micro switch hooked up to a relay, but next step is to put the line lock on its own separate switch. Its never popped out of OD since we had the brain box removed. Just goes INTO OD by itself every so often. With all the money spent on a custom CNC made shifter housing for the thumb switch, routing the shifter handle to hide the wire & modifying the H pipe for the GV unit, it'd be a shame to remove it all now. The guy who's fixing it also has a GV in his stroker Charger & has had no issues after removing his GV brain box. Finger's crossed...

There's a relay installed & I also suspected some kind of RF issue, but once we take the line lock off that switch & dedicate the micro switch to the OD, I'm hoping problem will be solved.

Dave at GV told me stroker motors take more juice from the battery when starting & if the battery dips below 12.7 volts, the GV brain can go into "stupid mode" & shuts off. We even changed the pos wire to the Optimas to a 00 welding cable & it didn't make any difference. I feel like we were in stupid mode to buy the GV in the 1st place, but with all the hype on their site about being able to split gears & go faster, it seemed like the cat's meow, but turns out that's only for automatics with a GV. For us, it serves as an OD 5th gear only.

That's what I was thinking & was afraid could be the problem. We had a custom housing cnc'd for the switch & mounted under the shift ball as well as the shifter handle routed slightly to hide the wire, so that wasn't cheap. All the on/off switches to the GV, line lock & elect fans were installed in the ash tray, so I'm hoping disconnecting the line lock from the micro switch will be the fix.

I've had the issue on occasion where the unit shuts off after start. I also assumed the voltage was dropping to low under start conditions so my solution was to install a separate switch to control the 12v power to the unit. After I start the car I can flip the switch to turn the unit on. No more low voltage situation as the car is already running.

I have 3 of them. All are used. (64 riviera, 67 coronet, 79 camaro) The oldest one had an analog brain box (64 riviera) and I had no issues with that. The other two have the digital brain box and I can have a problem if I turn on something with a high electrical load.

I was talking to some companies that have have gps speedometer senders that have relays built in to automatically turn on and off at certain speeds. So far the prices were a bit high for me to pull the trigger on anything.

As for vibration. (79 camaro) only one of my cars has a problem. Vibration gets bad at 65 and goes away after 75. I've had the shaft balanced twice at a driveshaft shop and each time it got better, plus I checked the angles and all is good. Thinking I need the shaft balanced at a driveshaft shop that does high speed balancing. Most driveshaft shops don't have the capability to balance over 900rpm.