hey yall i got a 04 f150 flareside with a 5.4 and 3:73 gears on 37 mud grapplers now i don't drive alot on the hwy but when i do at 50-55mph my rpm are around 1050-1100 is this to low of a rpm . Im aware i dont have any power to pass unless i get about half throttle to kick it out of over drive but that doesnt bother me . But the truck does not jump in and out of over drive so i dont see a problem and the motor is at a lower rpm which means its not working as hard correct if i seem to be on the wrong train of thought please feel free to steer me in the right direction .


thanks

 

Is it low? YES
Is it a massive concern? Probably not.

Your truck would probably benefit from a gear swap. 4:10s won't change it much, but a 4:56 or 4:88 would certainly make it more peppy, but it'll raise those RPMs too.

 

its it putting to much strain on my tranny ?? and is it hurting my gas mileage

 

Yes and yes. To what extent is out of my knowledge base.

 

If you kick it out of OD manually the truck will be much happier at that speed. Anything below 1500 RPM seems to bog the engine which will make it strain harder and run hotter and will probably carry over to transmission. Heat is the #1 damaging factor relative to transmission failure. And when you bog the engine you are increasing the risk of detonation. Detonation with platinum plugs is not a pretty site.