Increase MPG by 50-80% with a cold vapor fuel system?

[Edahall]

Originally Posted by kikkegek

wow! nice mileage.

how do you recognise a 4wd version from a 2wd?

Even a heavy Suburban can get good fuel economy if equipped correctly. Only problem is in the states, diesel has been significantly more expensive than gasoline the last while.

If you do put in a 700r4, make sure you get a 1987-1993 tranny. They were a better overall unit.

2wd


4wd

[lilpoindexter]

I hook a tube up to my butt, after eating burritos, and I can go for 47 miles without touching the gas pedal

[kikkegek]

Originally Posted by lilpoindexter

I hook a tube up to my butt, after eating burritos, and I can go for 47 miles without touching the gas pedal

hehehehe....so you run bi-fuel? Propane?

[78 Chevyrado]

I don't know if the heavier tires would offset any gains had by blowing them up to higher psi. you could get some skinnier tires though, like 235's or less (as skinny as you can stand) and air em up. that will help more I think, just getting skinnier tires, and get them about 29" to 30" tall.

[Goldfinger]

4wd 700r4 has a short shaft while the 2wd version is much longer

[kikkegek]

Originally Posted by Goldfinger

4wd 700r4 has a short shaft while the 2wd version is much longer

so, can I buy any 700R4 and do I need to find a seperate longer shaft, or is that directly connected to it?

[Edahall]

Originally Posted by kikkegek

so, can I buy any 700R4 and do I need to find a seperate longer shaft, or is that directly connected to it?

I would highly recommend looking for a 2wd version 700R4. The 4x4 tranny has a shorter output shaft and will not work in a 2wd application. You would need to locate and install a 2wd shaft for this to work. You need to tear into the tranny to do this. It can be done but it's more work then it's worth.

[kikkegek]

@Edahall: thanks for the info.

sorry for the misunderstanding guys. I have a 4WD. So I will need to look for a 4WD version.

probably no way I can get one over here in the Netherlands.

Anybody got a good one for sale here?

[GmtGmt]

Try Osby Skrotten en sweden Peter is always ready to help

http://www.bildelarosby.se/en

[69CST4x4SWB]

How hard is it to swap out my old 4 speed with granny low to a 6 speed in my '69 K10 which I believe has the NP205 transfer case? I hope I got that right! Also, what could I get the 6 speed out of so I know what to look for? Thanks!

[Edahall]

Originally Posted by 72_GMC_Sierra_Grande

How hard is it to swap out my old 4 speed with granny low to a 6 speed in my '69 K10 which I believe has the NP205 transfer case? I hope I got that right! Also, what could I get the 6 speed out of so I know what to look for? Thanks!

Are you wanting a 6 speed manual or 6 speed automatic? I'm using an NV5600 6 speed manual in my 1990 Suburban with a NP205. There are others such G56 and ZF6. The NV5600's were offered in Dodge Cummins trucks from about 99-03. Afterwards, they went to G56.

[69CST4x4SWB]

Originally Posted by Edahall

Are you wanting a 6 speed manual or 6 speed automatic? I'm using an NV5600 6 speed manual in my 1990 Suburban with a NP205. There are others such G56 and ZF6. The NV5600's were offered in Dodge Cummins trucks from about 99-03. Afterwards, they went to G56.

Yeah, looking for a 6 speed manual that will bolt right up to my NP205 and hoping to not have to make any or at least little modifications to anything!!! Maybe what I need is a complete unit trans/transfer case and just swap it all out together!?

[Edahall]

Originally Posted by 72_GMC_Sierra_Grande

Yeah, looking for a 6 speed manual that will bolt right up to my NP205 and hoping to not have to make any or at least little modifications to anything!!! Maybe what I need is a complete unit trans/transfer case and just swap it all out together!?

The NV5600 is one of the transmissions that will bolt up to an NP205. However, it's still much longer than the SM465 4 speed manual in your truck. That would mean making driveline changes and moving the crossmember back. You'll also need an adapter from someplace like Advanced Adapters to be able to mount it to your engine.

The other option might be to use a 6-speed ZF S6-650 manual out of a 2001 or later Chevy 4x4 truck with the 8.1L. The advantage here is it would bolt right up to your 350. However, GM didn't sell many 8.1's to begin with and finding one with a 6 speed manual is going to be even harder. Most people opted for the Duramax and Allison transmission.

Why are you interested in a 6 speed? Do you do a lot towing? If you do a lot of heavy towing, having that close ratio makes a huge difference. If you're just looking for that extra gear for better cruising, consider another option. Install 3.08 or 2.73 gears and stay with your 4 speed. My 72 Chevy 4x4 4- speed has 3.08 gears and it cruises very nicely at 75 mph.

[kikkegek]

I ended up swapping my TH400-NP208 for a perfect swap in one day for a TH700R4 with NP208...even the crossmember was already in the correct spot.

waiting for first mileage results now

[andrewmp6]

Have you looked in to a diesel swap tho ?

[69CST4x4SWB]

Sounds like I've got a project on the horizon!!! Thanks