trans or rear end ????

[apachedaddy]

what to do what to do, please chim in on this.... I have a 350/350 in the 66 and was wondering if i should go with an AOD trans or better gears for the open road.... I have a local place here in savannah GA that will rebuild the old 12 bolt (posi trac/gears/and new 5 lugs axels/and all new guts) for $1400... Was thinking around a 3:08 gear or maybe a little taller.... OR a AOD trans that i could get a kit or try and put together from the PAP yard... Either way i go on the trans it could cost me alot more in the long run... If you had your choice what way would you go.... I do about 50/50 in town driving and on the road... Thanks for your input....

[Slow Build]

I'd say throw a 700R4 in it with 3:73 gears running about 28" tall tire.
I liked that setup on my 89. Great around town, good on the freeway and I could tow my boat to Tahoe with no problems.

[kalirodding]

I agree about the 700. Thats what I got for my 55. I know a lot of guys run the 350 trans but not sure why. Can't beat that extra gear on the 700.

[markeb01]

I lot depends on how many miles you put on the rig every year. If it's 50/50 local highway but only sees 5,000 miles a year, the investment considerations would be different than if you drive it 50,000 miles a year.

Before I swapped to a T10 4 speed, I ran a Turbo 350 for over 10 years and thought about switching to a 700R4 for gas savings. I read several articles that summarized - if you're changing from a 350 to a 700 just for the gas mileage improvement, it will take years and years of gas savings just to break even on the initial conversion cost.

However if the extra gear, less engine wear and comfortable cruising are worth it, and especially if you do a lot of driving, it still is a nice improvement.