Being in California, the speed limit when towing is 55.
In OD, the rpms barely reach 1700 @ 55. In D, rpms run 2600 or so.
There seems to be little power at 1700, but even less at 2600. Feels plenty strong from say 1800 to 2400.
I am considering a 'box' to increase power in either rpm range.
Will increasing the torque at lower rpms kill the overdrive in the trans?
I am also considering taller tires, 255/85 from current 265/75, to drop the rpms in D and just not using OD to tow. Maybe this is a better idea as I don't have to mod the rest of the drivetrain.
The previous owner had the trans rebuilt, he said "it has a high performance torque convertor and stuff", but was not specific.
Thanks for helping me become less confused .

 

Speed up just a bit. I got a ticket in CA last Turkey day and talked to several truckers that told me CHP wont bother you till you go over 62mph. I am not giving you legal advice by any means, but I kept it there and other than holding up traffic I wasn't bothered by CHP anymore and there were plenty out there

 

I tow at 67mph all the time with my camping
trailer. It puts me at my "sweet spot" of 1900 rpm
in 6th gear. Thats where I seem to have the most
towing power, but I'm not stock either

 

With mine, either trailer (44' enclosed goose is 12,000# plus load), I am comfy at 1900 RPM - about 62MPH - also gets better fuel mileage. I do have some mods, but Superchip is always (only) on tow-performance.

 

Or get an underdrive unit.

 

If you really need to change something, I would just get some taller tires and run in 3rd gear.

 

An Edge EZ would be my suggestion. I love mine. I tow about 9000# worth of RV. Mine's a 33' travel trailer, not a 5er.

With the EZ, I run in OD at about 65mph. Only downshifts on the bigger hills.

 

TXTad is an underdrive avail for an auto? If so I would love to have one for mine.

 

I'd say get an EZ or something that has a boost fooler or for that fact just get a J-hook. It sounds to me like your defueling at the higher rpm.

 

or you can get rediculous gears like my 02 and turn 2200 in od at 60 and not have any prob with lugging at all

 

You've got 4.10's? I run 60 mph 1900 rpm's(running 26570r17's) cruise control set all over the state! This should get you closer to the sweet spot and help with your mileage.

Rick

 

I've got something like 4.63's in the rear and 4.56 in the front. 1st gear is useless even with a trailer. I only use 1st to pull fords out so I don't slip the clutch

 

I have 4.10, tow 16,000 with a six speed and have no problem on level ground at 55mph. Get great mileage at that speed. I sure don't try to push it at that speed and will drop down if I hit a hill.

 

Gee, I sure hope not. Transfer cases are pricey.

 

I would venture to say you have 4.56 front and rear. If you have different gear rations in either end then you are going to blow up your transfer case.