Update from GV: Per Nick (maybe ****) both "intermediate" and "main" driveshafts need to be shortened for 2wd ZF (non drive line parking brake) units that they offer.
Experience with GV install anyone?
- Thread starter Kizer
- Start date
My '90 SC had a 3.54LS, and was in bad tune - compared to my '91, REALLY bad tune. I towed a '48 Ford Club Coupe on a car hauler, 5,000-6,000 lbs, and had no issues. I say install the 3.54 gearset and a turbo!
That motor can take 2800-3000 RPM just fine, although it's not at peak efficiency.
Eli
Garbage_Mechan
Garbage Mechanic
I have a GV in the 86 2wd 6.9 NA, C6, 3.54. In this app coupled to the rear of the C6. I love it. In this app on hilly country 2nd gear overdrive was very useful.
For a ZF 2wd truck I would prefer the divorced unit if possible. The adapter for GV is a trans tear down to install for direct coupled. If you put one in keep your old driveline intact you you can remove it for repair and not be down.
For a ZF 2wd truck I would prefer the divorced unit if possible. The adapter for GV is a trans tear down to install for direct coupled. If you put one in keep your old driveline intact you you can remove it for repair and not be down.
Garbage_Mechan
Garbage Mechanic
For a ZF the gear splitting is a little harder and less useful than the C6.
I agree but I'm chasing final drive ratio and I've got a LOT of time behind the wheel of a "bolt action" truck.
Also, I was thinking that with the GV, I might still swap the 3rd member gear set or go to 19.5" wheels with 225/70's ... then the gear splitting would be great.
Garbage_Mechan
Garbage Mechanic
THE place to go for units, parts, or a good chat about them is maximum—overdrive.com out of Point Aromas Ca. He even makes his own control box. He swaps adaptors, rebuilds, sells units and parts. Gear Vendor really doesn’t care much anymore almost an annoyance to them. There is a divorced unit private sale on EBay right now....
Exactly the plan, if I go with a GV. I already have intermediate shaft, new carrier bearing and main shaft on hand from another project.
Garbage_Mechan
Garbage Mechanic
Gear Vendors are expensive but I don’t think they will ever go down in price so they can always be sold again later to get $$ back if no longer needed......
IDIBRONCO
IDIBRONCO
Wes, you sure do go to Mexico a lot. Do you have a girlfriend down there on something?
Once in a while those split gears on a zf are nice to have.
Garbage_Mechan
Garbage Mechanic
Yep thinking about it 3rd over might be useful. With a manual I’d rather have a brownie, a dne/US Gear or a Mitchell but unicorns can be hard to find lol.
Unicorn indeed! I've been looking for alternates to GV and haven't found much.
I looked up Maximum Overdrive. I'll give them a call next week. I appreciate the lead.
Garbage_Mechan
Garbage Mechanic
Over the years there have been some knowledgeable folks over on 4bt swaps that really know brownies. There were some good ones made just before the end of the era. Think what you could do with a under/direct/overdrive. Brownies were all about pulling a load with little horsepower. Like a 302 gas GMC six cylinder doing 60,000 lbs.
IDIBRONCO
IDIBRONCO
I knew there was a 302 V8, but I hadn't heard of a 302 6 cylinder before. I guess I learned something today.
Garbage_Mechan
Garbage Mechanic
It was really GMC’s claim to fame post WW2 through 59 I believe. The GMC V6 replaced it. It was in the WW2 GMC army trucks too. Very tough. A 55 GMC pickup was a lot more truck than a Chevy. There were also legendary Wayne 12 port heads and other speed parts. After the SB Chevy V8 got easy to get they kinda faded but still have a nostalgia following.
