Gear Vendors overdrive

[DavidD]

Hello fellow members, I would appreciate any input from members that may have the Gear Vendors under/over drive. This sounds like a great unit but it would be wise to have some input on its reliability and quality. All replies will be apreciated.

Dave,



98. 5 24V,5sp, BD plug-in-power,BD brake, Exhaust, 275 injectors,

dd boostmod. , rancho9's, 315's, piaa lights.

 

[Shooter]

GV Quality and service is great. have about 25k on mine. IMHO if I had a stick I would probably opt for a US GEAR. You will get a little better 4 - 5 split with the USG, you can use your e brake in od with USG: GV will auto shift out of od when e brake is activated. USG will split 4x4 high or low range.

You can not shift USG into od under wot, GV you can.

 

[Paul]

I would say it is well worth the money spent if you do any towing. I found customer support to be very good.

 

[DavidD]

E-brake

I appreciate the response to my question but i have a little troble understanding why the GV would kick off when the e-brake is applied? Doesnt seem to have anything to do with the e-brake am I missing something here?, Dave

 

[Evan A. Beck]

NEVER use the E-Brake when the GV is in OD. I have seen them fail due to the driver operating the brake while in OD. IT will literally fry the clutches in the OD unit. Also, the GV does not automatically disengage when the E-Brake is activated. It could be wired to do so though.

 

[illflem]

I was once told that most all OD gearboxes are noisy. Is this true?

 

[Evan A. Beck]

The GV is silent while in operation. When it shifts on automatics, you can feel it, but it is not obtrusive. In the GV electronics, it actually unlocks the TC when it shifts. Pretty cool technology. On a manual truck, you can shift it real easy without the clutch.



The GV can be activated at any speed above 20. This is because the internal pump works off of shaft speed. It works much like an automatic transmission in that shifts using hydraulics. Pressures usually stay at about 600 or so, and if the unit is low on oil, it will not shift.



They are pretty cool, but very expensive @ $2,500.

 

[JSchooley]

I had a GV on my last truck and loved it. I think it is a reliable and well designed unit.



The reason for the E-Brake logic is due to the clutch design in the GV. The gears are cut so that more pressure is applied to the clutch when more torque is applied to the transmission. The reverse is also true. If you have enough retarding power from the brake, the pressure on the clutch will be reduced to the point the clutch will slip and fry itself.



I did not have the logic in mine that prevented applying the brake when GV was in overdrive, and I occasionally applied the brake when in overdrive with no problems, however it was never at high RPM where you get the most braking action.

 

[Turbo Thom]

With the US Gear The shifting clunk is noticable but is a sign of proper shifting. Yesterday we had a get together at STP in Conley, Georgia and one of the memembers wanted me to show him how the unit shifts. We left the lot and drove about 500 yds. and I told him I had just shifted 7 times. He looked at me and said," no way". Then I had to do it over and slower. This time I went through 10 speeds and applied the de-celerator brake. He was impressed and went back to the group with a big grin on his face. He tows a horse trailer with 2-4 animals in the mountians.



With the USG you are on your on. You do all the shifting at what ever point you want. It uses an electric motor to pre-load the shift spring, you apply the clutch and there it goes. Shifting is the same as 2 speed rear axle.



I'm sure a GV is a good unit but I wanted a positive shift for my 5 speed. I'm used to it , like it and won't go back to 5 for towing.



Preston

 

[rob10858]

another view on od's

ive said it before, and i'll repeat my caution. these od units are fantastic when they are working properly, but when they fail, it can be a big headache and expense. we started putting both the gv and us gear units on all our trucks in 96. [all manual] this included 454 chevys, v=10 and ctd dodges and psd fords. good results pulling constant loads for about 50,000 miles and then disaster. i wont trash either brand because we were always treated well with any problems. but, the end result was, well, not up to my expectations. none of them lasted for over 75000 miles, with all different excuses why. fluid, seal, drivetrain problems {the drive shaft has to be shortened to accomodate both units} evan, isnt that correct? in the long run weve taken all of the od units out and gone back to the 5=6 speed configurations. with the drivetrain mods this isnt cheap. ill leave my e mail notification on , if someone can explain this failure rate, then please let me know. like i stated before, i have no problems with the service, just the product.

 

[amsoilman]

what to buy?



Sounds like both units are good quality transmissions. The question is which one to buy? I am a bit confussed

on the instalation of the USG unit. It sounds like it goes between the transfer case and the trans. This seems

loke it would require a lot of modifications to install but it would work in all ranges IE low and high and 4x4.

The GV on the otherhand mounts behind the transfer case and all you do is shorten the drive line. Which

would be you reccommendation. I tow a 4 horse 10,000# trailer and I have a bd-exhaust brake. The issue wit

the brake is not to critical as being able to pick the right gear for climbing the hill. Looking forward to you

input, Thanks Dave in NevadaThis thread was mistakinly entered as a "new" subject by DaveD. He asked me to move it here.

 

[pcorssmit]

US Gear sounds like what I'd want, something that is completely driver controlled. I like the idea of being able to split all the gears and use an exhaust brake as well. There are a lot of times towing lighter trailers when I'd like to start out somewhere between 1st and 2nd. I'd really like to get my cruising rpms down as well, but have a feeling it'll be some time before I'm able to seriously consider an OD.



Pete

 

[rob10858]

i'll amend what i said before. the us gear units were pretty reliable, [the only real problem we had with them were speedometer related] our two chevy gassers had them, the us gear units never failed, but the rear end and trannies on both trucks more or less disenetgrated after about 35000 miles. i think that this was due to the fact of chevy trucks long history of weak drivetrains trying to keep up with strong powerplants. they do shift much rougher than the gv unit, but its like the 6 speed trans in our new ctds, once you learn the right rpms and gear patterns, you can go into od with ease. i feel that the right od system depends on how it will be used . if you pull heavy and alot go with the us gear, if you pull light and every now and then try a gv. just keep the paperwork in your truck .

 

[Paul]

If you have a 4X4, standard lenght wheelbase truck [ not the ext cab with 8' bed] , the fuel tank must also be shortened to use the US Gear OD.

 

[Doubleclutch]

OK, here's my $. 02. I have a GearVendors unit and am very happy with it. I was planning on getting the U. S. Gear but I have a standard cab 4x4 and didn't want to make the compromises necessary to use it (modify both drive shafts, replace fuel tank with a smaller unit and have my shift levers moved back to accommodate the OD). The GV gives about 500 rpm reduction between third and third-over, fourth and fourth-over. There isn't much difference between fourth-over and fifth gear but this will give better fuel economy while driving home after the fifth gear retaining nut goes on vacation. The only minus is the unavailabilty of second-over due to the 20mph (600psi) requirment. With regards to the exhaust brake- I have a PacBrake but the Eaton switch is the same for BD, PB and GV. This Eaton (red push/pull) switch has three terminals on it. The bottom terminal is hot when the OD is off (in), so I wired the unused bottom terminal to a headlight relay, which switches the ground on and off to the PacBrake solenoid. With the GV engaged (switch up) the ground on the exhaust brake solenoid goes away and the brake stays open. This way, when the OD is in service, the exhaust brake isn't. OOPS, it looks like that was more than $. 02 Sorry!

 

[DavidD]

Packman, You have me concerned about the longevity of the unit( USG). I would really consider one of these but of course I would like it to last a good while. I have invested alot in the truck and the gears are about the only thing I am not happy with. Would you say the USG would be a reliable unit if well cared for and towed a 10,000# trailer. We live in a mountainous area and I am always towing over 8-9K foot passes. These OD units sound great just concerned over spending 3K on something that might break after 50K mi. Thanks for everyones input on the subject, Dave