truck bad on highway

[88mudder]

i have a Ranger with a 302, 4.10 gears and 35" tires with the AOD 4 speed OD trans. On the highway going 70mph the truck struggles to gain speed and always wants to kick into 3rd and the rpm's run high in 3rd..i have some sort of mild cam that doesnt affect the idle but it rips in the midrange up to about 4 grand. In OD it will cruise up to about 80 no problems but the RPM's are low and the truck won't gain speed unless it hits 3rd gear banging the limiter pretty much. Is this normal? I think i have the wrong cam but not sure or maybe i need 4.56's? Any help is great the truck is a blast!

 

[JamesC]

I am guessing its a low vacuum thing because of the cam. causing the transmission to think your under load.

 

[bobbywalter]

whats the build and induction of the engine?


whats the tv and pressure setup? did the trans get built with drive-overdrive? what governor and converter?


normal 302's wont push 410 and 35's with an aod. believe it or not a soilid 4.0 will do better then the normal wheezer 302's at that rpm.. best bet is 456 gears if the motor is a turd but thats only IF YOU can set up the gears yourself.

its that or tune/build the engine for this job.


456 was too deep for my rig and 410 was just right for freeway cruising, but 456-488 gears are sweet for wheeling.

 

[bobbywalter]

what do you mean rev limiter?

at 70 it should be @ 3 k in 3rd and @ 2 k in od.

 

[88mudder]

Tv pressure was off..causing it to kick down when i wouldnt try passing or hitting it. Runs like a raped ape now. Very glad i stuck with the 5.0 and cammed it. All the 4.0's ive driven perform like a 2.9 with a ported head... Not good with 35's and bigger. Well thanks for the help.