th350 overdrive unit

[mtnbiker727]

I've been thinking about getting an overdrive unit for my truck. My little Pontiac gets 38 miles per gallon, so it's kind of painful to get 150 miles per tank in my truck... It's like a Sunday go-for-a-drive truck... but I plan on taking it on vacation... so I'll probably be ~1,000-2,000 miles per year. I'm pretty sure it's not worth whatever the price may be... but I'd like to hear what you guys say...

Where can I even find the parts? and how do I find someone who can install it?

This last tank of gas I got 14.28 miles per gallon, so I guess I'd probably have to get at least 20 mpg to make it pay off in like 25 years.

Any thoughts or comments? Has anyone ever had one installed?

 

[HotRodPC]

I wouldn't be complaining with 14mpg. But you're on the right track. It's really not worth it if that's all you'll drive the truck.

You might get lucky and find a steal deal on an old motor home that has a gear vendor unit in it, but even then, just the work to adapt the gear vendor unit can be a bit pricey. As far as buying a new Gear Vendor unit, very pricey. Cheapest option would probabaly be a 4L80-E trans with an aftermarket stand alone controller.

 

[skysurfer]

There was a similar discussion on the payback of the GV unit and other options here: http://www.gmsquarebody.com/forum/showthread.php?t=3137&highlight=gearvendors

 

[89Suburban]

(((((((Sky)))))))


Posted From Hell

 

[mtnbiker727]

There was a similar discussion on the payback of the GV unit and other options here: http://www.gmsquarebody.com/forum/showthread.php?t=3137&highlight=gearvendors

Thanks Sky.

I figured there was probably a discussion about it at some point. I guess I would have had to dig back through the threads to last year to find it.

I guess I'll just be happy that I get 14 mpg and enjoy the ride.

 

[bucket]

You can try to do some little things to help improve mpg some, but 14 ain't too bad. Was that mostly around town or on the highway? Do you know your rear end ratio?

 

[mtnbiker727]

You can try to do some little things to help improve mpg some, but 14 ain't too bad. Was that mostly around town or on the highway? Do you know your rear end ratio?

That's mostly highway... with a little pressure on the pedal at times because I like to hear the Quadrajet kick wide open. :-D

I don't know the ratio... I'm not even sure how to figure that out. I'm sure whatever is there came with it from the factory, because the previous owner didn't change anything.

 

[HotRodPC]

You can visit the Squarebody Library, here on the forum. There is a thread with all the rear end codes and tells you where to find the code on the axle tube. This should be accurate IF YOUR CERTAIN, it's never been worked on or changed out.

 

[Driver4r]

Damn..... Ide love 14, I pull 6 out of mine, and occasionally 8. And mines my DD......

 

[bucket]

Damn..... Ide love 14, I pull 6 out of mine, and occasionally 8. And mines my DD......

Either it runs rich or your foot is always to the floor. Or both, lol.

I used my '77 K5 for a DD for a little while. It was a mild 350 that ran rich at lower rpm and I never could lean it out, but I still got 10-12 out of it. 9-10 if I played around much. With 33's and 3.08's it was a dog off the line, but once it got rolling it was actually pretty quick.

 

[HotRodPC]

Damn..... Ide love 14, I pull 6 out of mine, and occasionally 8. And mines my DD......

You got something wrong with yours. I get 10 city, 13 hwy with my 454/Th400 C20 and I know it can do better. I expect it will do better now that I have the new dizzy and plug wires. When I get the Carb adjusted after removing the EGR valve, replacing the balancer and timing the motor, I"ll expect 11-12 city and 14-15 hwy.

 

[Driver4r]

Weve covered this befor about why my milage is so bad..

 

[GreaseDog]

I've been thinking about getting an overdrive unit for my truck. My little Pontiac gets 38 miles per gallon, so it's kind of painful to get 150 miles per tank in my truck... It's like a Sunday go-for-a-drive truck... but I plan on taking it on vacation... so I'll probably be ~1,000-2,000 miles per year. I'm pretty sure it's not worth whatever the price may be... but I'd like to hear what you guys say...

Where can I even find the parts? and how do I find someone who can install it?

This last tank of gas I got 14.28 miles per gallon, so I guess I'd probably have to get at least 20 mpg to make it pay off in like 25 years.

Any thoughts or comments? Has anyone ever had one installed?

150 miles to a tank, and 14+mpg don't add up... You're got a 16 gallon tank at worst.

 

[Jims86]

150 miles to a tank, and 14+mpg don't add up... You're got a 16 gallon tank at worst.

Yup...I would do a compression check before adding an OD unit, which could make MPG worse with a worn out engine.

 

[Jims86]

I've been thinking about getting an overdrive unit for my truck. My little Pontiac gets 38 miles per gallon, so it's kind of painful to get 150 miles per tank in my truck... It's like a Sunday go-for-a-drive truck... but I plan on taking it on vacation... so I'll probably be ~1,000-2,000 miles per year. I'm pretty sure it's not worth whatever the price may be... but I'd like to hear what you guys say...

Where can I even find the parts? and how do I find someone who can install it?

This last tank of gas I got 14.28 miles per gallon, so I guess I'd probably have to get at least 20 mpg to make it pay off in like 25 years.

Any thoughts or comments? Has anyone ever had one installed?

FYI, my 86 K10 Burb was EPA rated at 15 MPG new. So dont balk at 14 if thats what you are really getting, especially with a 3 speed.