Better gas mileage suggestions.

[lt1fire]

NV4500 is a great choice, but it's awful spendy. About $1k for a good used one and $1,200-1,400 for a rebuilt. Then you have to adapt it to the Toyota tcase - about $700 to your door. 2 large buys a lot of gas!!

50-0213 | Engine & Transmission Conversion Adapters - Advance Adapters

R

but you get the satisfaction that you now have a better rig and that is priceless.

You can always skip the toyota t-case and run a gm one.

He will also make up some money with the same of the 421 and the adaptor he already has.

 

[mtweller]

If you run a GM tcase, you have to deal w/ the passenger offset axle. Trust me, I have researched this issue to no end when I was considering a SBC conversion a couple of years ago. It's the way to go, but there is no cheap way to do it. I wanted a NV4500 BAD! Martin is putting one in his diesel convo, so he will know some specifics. Might have changed some since I was in the loop.

R

 

[SFROMAN]

What is the negative effect of a short drive shaft? I guess since I don't know enough about this tranny it's hard for me to weigh the pros and cons. I do know that I want to continue to improve on the drivability of a 40 year vehicle to make it as enjoyable and comfortable as posible whether it be on the road as a daily driver or on the trail.

 

[mtweller]

The shorter the driveshaft, the higher the angle between the pinion and tcase o/p. More prone to CV (Cardan joint to us Toyota folks) wear and tear and vibration. You would absolutely have to run a Double Cardan in lieu of a u-joint style driveshaft. Those can be had from some minitrucks pretty easily - that's what I run front and rear.

R

 

[mtweller]

Double Cardan joint:

 

[SFROMAN]

I have seen the shorter driveshafts on cruiser with automatic tranny 700something not sure the actual name. Anyway I def want to avoid that. The sm420 is going to have to do for the time being I guess. I suppose a cheaper and easier fox would be to drop the second tank and clean it out. You see I only use the tank under the passenger side which I believe is a 15 or 20 gallon tank. The second tank in the rear is I believe a 30 gallon tank but I don't use it because the last time I switched to it, it made the truck sputter and tugg pretty badly. I believe the cause is old gas or dirty gas or both either way if I fix that I would not have to gas up for at least two weeks or so. I think Jason recommended an online electric pump. I will probably attempt this plan of action. It might not get me better gas milage but at least it will get me further between fillups. I will look into improving my ignition and a fuel injection swap in the near future.