Tranny
Cargo Master
Joined: Aug 2007
Posts: 2,558
Likes: 69
From: New Zealand
As good as NP435's & T18's are, they won't help much with this problem because top gear is still only 1:1, the same as your auto. The only advantage is no converter slippage (& a little less power consumption) - this will help with gas a bit, but not rpm's.
New User
Joined: Aug 2010
Posts: 12
Likes: 0
From: Greenfield, CA (Monterey)
Tranny
I had a 71 F-250 4X2 warmed up 390/ 2BBL, C-6 with B&M shift kit and it averaged 16 mpg. It was very reliable, I pulled alot of chevy's and heavy trailers with no problems.
I am currently building the same combo for my 71 F-100 4X2.
I am currently building the same combo for my 71 F-100 4X2.
Junior User
Joined: Aug 2010
Posts: 79
Likes: 0
From: Falconer
Mythbusters did a fuel mileage episode and found that trucks did best with tailgate up because of the "Push effect", also at 55 mph vehicles did better with windows down compared to those running ac with windows up. Sorry, no advice on a tranny.
4wd High
Joined: Sep 2010
Posts: 9
Likes: 0
Sorry for buttin in, but I have to say something here. I have a '72' F250 Custom with a 300 ci six, C4 tranny (original) and 160,000 miles. My dad bought it new and I inherited it 20 years ago. Max speed was 55 with a 4.11 rear end and tall 16 in wheels, and it got about 14 mpg empty or with a 3500 lb camper. Got tired of going so slow and switched out the rear end for a 3.73 from the same year and model. Now can do about 65 - 70 with the same mpg due to the aerodynamics. Speedometer doesn't read right though. I'll fix that when I replace the worn out C4...to what I don't know, which is why I am here. It's hard to find C4's or C6's where I am, and I'm not certain I want to go to the trouble of switching to a manual.
The truck looks like hell, rides like the axles are welded to the frame, can tow a mountain, and starts every time. I love it, and will never get rid of it.
The truck looks like hell, rides like the axles are welded to the frame, can tow a mountain, and starts every time. I love it, and will never get rid of it.
Thread
Thread Starter
Forum
Replies
Last Post
