experience with gear vendors over/underdrive anyone?

[foamypirate]

I am in a different boat, but considering the same options. I have an '84 K3500 crew cab 454 w sm465 (bombproof, but super wide ratios and no overdrive).

I considered the gearvendors O/Udrive ..... but $3.1k plus another $500 for a new driveshaft is a lot. $3600 is a lot...

I want to to keep the manual but i am looking at some 6 speed options.

The only reason i like the O/Udrive is the fact that i will essentially have 7 gears (possibly 8, but they dont list low over, i assume the torque may be too much for the unit)

BUUUT ... overdrive at 0.78:1

IF i go with a NV5600 (adapters were once made, possibly have to source a custom one now), i can get a slightly better OD at 0.73:1 and i still get a good low ratio and better gear splits. but $3600 for a rebuild with a $2000 core charge is a too stiff ... $5600 is a bucket of money.

WAHT I REALLY WANT THOUGH .....

is to go with a ZF S6-650 from a GM ... hard to find, but it should bolt up to a BBC with gearing nearly identical to the NV5600 ... but the overdrive is a few percent taller at 0.72:1. $3200 plus a $1500 core charge is still a lot at $4700 bucks

Now with all that said ... i think a 5 speed would be a great improvement, and easy to source, but a 6 speed would be amazing to me. and if you really want to get a move on ... do the 6 speed swap and the GV O\Udrive ... double OD would barely sip the gas out of the tank!

I considered a ZF S6-650 before doing my NV4500. That bitch is TALL, which is why I tossed the idea. My LS swap mounts set the engine higher as is, so there was no way I'd be able to fit it without hacking the firewall and floor. It might fit in a truck with stock engine position; a small body lift would help.

The shifter is pretty much inline with the top of the bell housing:

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[Jrgunn5150]

The ZF will bolt to the big block, it was available behind the 8.1

I'm really a fan of keeping things simple though, and a 4500 is pretty simple lol.

 

[LGustin]

I will be adding a Gear Vendor to my square eventually.

 

[74 Shortbed]

I will be adding a Gear Vendor to my square eventually.

And you'll love it, dumbest thing I did was selling mine.

 

[Honky Kong jr]

I considered a ZF S6-650 before doing my NV4500. That bitch is TALL, which is why I tossed the idea. My LS swap mounts set the engine higher as is, so there was no way I'd be able to fit it without hacking the firewall and floor. It might fit in a truck with stock engine position; a small body lift would help.

The shifter is pretty much inline with the top of the bell housing:

You must be registered for see images attach

Holy hell that thing looks huge..... I guess it’s a ZF thing

 

[Affende]

I considered a ZF S6-650 before doing my NV4500. That bitch is TALL, which is why I tossed the idea. My LS swap mounts set the engine higher as is, so there was no way I'd be able to fit it without hacking the firewall and floor. It might fit in a truck with stock engine position; a small body lift would help.

The shifter is pretty much inline with the top of the bell housing:

I honestly didnt realize it was that tall. Im a sucker for more gears though... i love driving the 6 speed wrangler. it just feels right.

The other issue with the ZF is its length. the sm465 comes in at about 19.25" from bellhousing to rear output mating surface and the ZF is (reported differently) from 28-30"!!

The ZF will bolt to the big block, it was available behind the 8.1

I'm really a fan of keeping things simple though, and a 4500 is pretty simple lol.

I, too, was under the impression the ZF would bolt up ... thanks for confirming. it seems the biggest hurdle will be the clutch which will be an easy switch to a later model hydraulic setup

Holy hell that thing looks huge..... I guess it’s a ZF thing

i like 'em big!

And you'll love it, dumbest thing I did was selling mine.

did you have it behind a auto or a stick?

 

[74 Shortbed]

did you have it behind a auto or a stick?

TH400, gives ya 6 speeds.