OD worth the $ ?

[david85]

It is true that T-slip is not linear but with my 410's I will still be in the same efficiency range. Od will put me at aprox 26-2700 at 65. Now I am at 3150 which roughly calculates out to 9-10% slippage. I looked up a slip calculator and even at 55 I should be at about 2000, and that should keep me in the 10% range. Would I like a lockup? Yes and no. I like the simplicity of the C6, and it is in perfect shape, has no electronics, known dependability. Money was no object I would switch to a manual, but money is an object. Main objective is to not be screaming the motor so badly just to stay with traffic. It drives me nuts listening to it at 65 mph. Any MPG gain will be a bonus. If I had 355's I would not have a problem and would not need OD. Looked at doing that and it is cheaper, but I feel that would be too much with this motor and a 7500 pound weight on an all around basis. Will spend a lot of time putzing around the woods where the 410's will be nice. Just trying to figure out how to solve the RPM issue at a price I can afford. I feel like I am torturing the truck in traffic. thanks for the input, Larry

Yup, mine was 4.10s and C6 when I first bought it many years ago. I switched to 3.08 gears and it worked well for a few years like that. 1st gear worked better than expected for towing, but I rarely had to move more than 5000lbs. My truck was also a 2wd at the time, so swapping only one gear set is relatively cheap and easy compared to swapping both axles. Sounds like you have a 4x4, so the taller axle ratios aren't as big a problem, since you can always use low range to get a heavy load moving on a steep incline. When I still ran the 3.08s, the truck only lost "pulling power" below 20mph. Once moving, I simply held onto lower gears for longer and it seemed to perform better than with the 4.10s (yes I realize that sounds crazy). 2nd gear with 3.08s was almost equivalent to 3rd gear with 4.56, so it worked better on some hills. 3.55s didn't work as nicely though, and I find the truck gets caught between gears more often now.

Looks like GV overdrives are still available, but they aren't cheap brand new. Are you still seeing used ones in the wild?

Automatic C-6 3-speed - Gearvendors

BW 1356 Transfer case w/slip yoke.Replaces 6 3/4″ tailhousing.87-92 Ford trucks w/either C6, T19, or ZF.

gearvendors.com

 

[Black dawg]

Still see them pretty regularly around here, used.

 

[Dustyman]

Yup, mine was 4.10s and C6 when I first bought it many years ago. I switched to 3.08 gears and it worked well for a few years like that. 1st gear worked better than expected for towing, but I rarely had to move more than 5000lbs. My truck was also a 2wd at the time, so swapping only one gear set is relatively cheap and easy compared to swapping both axles. Sounds like you have a 4x4, so the taller axle ratios aren't as big a problem, since you can always use low range to get a heavy load moving on a steep incline. When I still ran the 3.08s, the truck only lost "pulling power" below 20mph. Once moving, I simply held onto lower gears for longer and it seemed to perform better than with the 4.10s (yes I realize that sounds crazy). 2nd gear with 3.08s was almost equivalent to 3rd gear with 4.56, so it worked better on some hills. 3.55s didn't work as nicely though, and I find the truck gets caught between gears more often now.

Looks like GV overdrives are still available, but they aren't cheap brand new. Are you still seeing used ones in the wild?

Automatic C-6 3-speed - Gearvendors

BW 1356 Transfer case w/slip yoke.Replaces 6 3/4″ tailhousing.87-92 Ford trucks w/either C6, T19, or ZF.

gearvendors.com

When I am on two tracks/back roads I spend a lot of time in that 10-20mph range and a lot of them are loose sand. Thats why I decided against a gear change. I do have low range, but it is kind of a pain its so low. Interesting on the 355's, that is the ratio that I was thinking of. Still have time to mull it over my shop is busy [Woodwork] right now and that comes first.

I won't be towing anything with this it is my camper/cabinet mover but still it weighs 7500# and is 8' tall. Has a nice aero cab to box thingy, but it is wider than the cab and 8'tall. Its fun, and I can work on it. My 2018, ya I don't know jack about new trucks. Its a rolling computer. Only computer on my 67 is the backup camera I just added.

If I go GV I will probably go new, the truck only has 10k miles on it so putting something on it half worn out just seems wrong.