Blown Gear Vendor overdrive

[Andy Perreault]

Today I let out the clutch going into second gear (I was on it pretty hard, merging into traffic), and BANG! The truck wouldn't move! I had enough momentum to roll over to the side of the road and come to a stop safely. I knew right away that it was the Gear Vendors. Looking under the truck, there were no fluids leaking, and the rear driveshaft was still securely in place. So, I shifted into 4WD and drove home.

I will not be getting the Gear Vendors rebuilt, I'm going to have it removed. Maybe someday I'll go with a U. S. Gear overdrive, but my budget won't allow that for now.

So, now my truck sits here dead, and it's my only mode of transportation. Well, I could drive it in front-wheel-drive, but I have a very long commute (over 120 miles round trip), and I don't want to do that.

I've been wanting to buy a used economy car to commute with for quite some time, so this is the perfect excuse to get going on that task. It looks like I'm going shopping tomorrow!

BTW, the Gear Vendors had about 75K miles on it.

Andy

 

[illflem]

Good reason to keep your old driveshaft intact and buy new ones when installing a gearbox.

Andy, good thing you have 4WD and the smarts to use it.

 

[Evan A. Beck]

Bummer, Andy!



What fails in the GV (most of the time) is the clutches. We had a 3500 come in on a flatbed the other day because of a blown GV. The guy had it replaced once, and this time he had us take it off. A lot of times what kills the GV is using it with the exhaust brake... Seen quite a few fail that way.

 

[John_P]

Andy:



Sorry to hear about your GV unit failing on you.



I have been thinking about putting an underdrive/

overdrive in my truck, but I don't know if I will

now. The units are really expensive and if yours

went at 75,000 miles mine would probably go

before that the way I drive. Do you know if the

U. S. Gear unit is any better?



-----------

John _P

 

[MikeR]

Hey Andy,

Have you called around to locate a new or used driveshaft yet? If you need to pick it up and take it back home,call me and let me know.

 

[Sled Puller]

I had a GV on an 1989 Cummins. They told me,"YOU CAN NOT HURT THIS UNIT. SHIFTING UNDER FULL THROTTLE IS OK. "





I traded it, but I always wondered about that. NOW WE KNOW!!!!!



Gene

 

[DAWG-1]

Need Help????

Hey Andy thats a bummer. E-Mail me if you need help at -- email address removed -- . I dont live too far away. Sam

 

[Andy Perreault]

Originally posted by MGM

I had a GV on an 1989 Cummins. They told me,"YOU CAN NOT HURT THIS UNIT. SHIFTING UNDER FULL THROTTLE IS OK. "

Gene

I wasn't shifting the overdrive, I was driving without it. Just letting out the clutch in 2nd gear and stomping on it... BANG! Just like a pro-stock car at the drag races, just get going and shut 'er down and idle down the track.

I've always been leery of that GV. It's made funny clunking noises since day one. If I had known then what I know now, I would have gotten a U. S. Gear. At the time I had it installed, though, U. S. Gear didn't make an overdrive for a Dodge 4X4.

Oh, well, what can you do? For now, I'll live without an overdrive. I will miss being able to split 3rd gear, but I can survive.

Andy

 

[Bob Wagner]

andy email me if you need a car

my neighbor is a mechanic and has a couple for sale for cheap



depends on your budget.

 

[Fast 1]

I was told by a gear vendor dealer that they would replace a boken unit for around $450. 00 and give you a new one year warranty. Might want to call gear venders and ask?

 

[Andy Perreault]

Thanks for the offers of help, guys. Fast1, no thanks, I want it off my truck so I don't have to worry about it anymore.

I decided rather than to rush into buying a used econo-box, I'll rent a car until the truck is running again. I'm supposed to be buying a house, I can't be blowing my money on a car! It would be nice, though, to have a second vehicle to drive around. My big Dodge isn't the most practical freeway commuter, and I hate to be putting all those miles on it (600 miles a week!). Maybe I'll still get one, but I don't want to have to buy one out of sheer desparation. A nerdy rental car will do the job this week.

I have always had good luck with used Honda Civics. But, trying to find a mid-90's 5-speed hatchback here in Seattle is tough, they're all sedans or coupes or automatics.

Another vehicle I'd consider is the boxy body-style Jeep Cherokee. A four-door would be versatile, especially since my Dodge doesn't have a back seat. I've searched for them, and again, 5-speeds are hard to come by. It seems like most of them for sale are red or have red interiors, and I don't like red!

But enough of my whining, the situation could be worse. I'm lucky that this happened before school starts in September.

Anyway, it'll all work out. It'll be a little bit of a hassle, but I'll have the truck up and running again soon.

Andy

 

[John]

man that sucks!

Sorry to hear of your Gear Vendors auxiliary transmission problem.



Let me know if I can help (call me or use my work email as my home PC is messed up at the moment).



With the miles you drive per week (although temporary), it would seem prudent to purchase a beeter econo box to commute to work. The fuel savings should ease the initial outlay for the vehicle in no time.

 

[Steve Campbell]

Evan, could you expand on why the construction of the GV does not hold up to an exhaust brake?

 

[RustyJC]

I'm not Evan, but I'll take a stab at explaining it. The GearVendors unit is a modification of the old Laycock electric overdrive as found on 50's and 60's Jags, Healeys, Triumphs, MGs, etc. It is a planetary system with a friction clutch similar to an automatic transmission. The problem is that this system is more efficient at transmitting torque one direction (from the engine to the rear wheels) than in the opposite direction (from the rear wheels to the engine, as when an exhaust brake is in use. ) This latter condition causes clutch slippage and ultimate failure.



The U. S. Gear system is a modification of the old Doug Nash overdrive - it actually shifts gears (just like a manual transmission) through an electric actuator/spring system. That's why, unlike the GearVendors unit, it can't be shifted under full load - you have to "untorque" it to allow the spring to make the shift.



By the way, U. S. Gear now has an application for the 4x2 NV5600 even though it's not on their website. If anyone wants the part number, let me know.



Rusty

 

[Andy Perreault]

Rusty JC hit the nail on the head. The Gear Vendors is not designed to be driven from behind. The place that installed my GV warned me not to use the exhaust brake with the GV on. They told me some guy just a few weeks before I was there burned up his GV in just two weeks, because he kept using his exhaust brake in overdrive. I kicked around the idea of setting up a relay in the exhaust brake circuit to lock out the brake when the GV is on, but I never tackled that project.

Andy

 

[John]

Update????

Anything new Andy?



Why not just add the US Gear O/D (or U/D) unit and be back on the road again? Won't it be necessary if you relocate (with trailer in tow) for several years as you stated before?

 

[Andy Perreault]

Re: Update????

Originally posted by John

Why not just add the US Gear O/D (or U/D) unit and be back on the road again?

What I'd rather do is keep an eye out for a 6-speed from a wrecked truck. Someone posted on the previous page that US Gear now has an overdrive for the 2wd 6-speed, I'm guessing that they'll eventually come out with a 4WD version someday. I can live without an overdrive for now. I need to get a house (and a garage!) first.

Andy

 

[Andy Perreault]

Well, I got my truck back today, no more worries and no more clunking and clanking every time I get on and off the clutch. Also, I recently bought a lil' Honda Civic, so now I won't have to wear out my truck driving up and down I-5 everyday.

Thanks for all the offers of help, guys. It sure felt good to get back behind the wheel of my truck again!

Andy

 

[Vaughn MacKenzie]

Originally posted by Andy Perreault

Also, I recently bought a lil' Honda Civic, so now I won't have to wear out my truck. . .

Uh oh, now Andy, don't get any ideas of buzzing up and down the freeway in that lil' tin can of yours weaving between cars and trucks, and cutting off big bad CTDs! One of them is liable to smoke-bomb ya!



Vaughn

 

[Barry]

The absolute finest combo for towing that I have ever had is the ETH/DEE/4:10s... . but, I will be the first to admit when I have to bob-tail 1,000 miles at 24 to 25 hundred rpm it's a pain. I have longed for 1 more gear when empty but the thought of dropping 3 grand at one shot is a little more than I can bring myself to do. And from the looks of this thread, I don't think I want a GV. How does the "other" unit hook up and what is the cost?