i am having an issue, where the truck wont drive faster then 40 mph or 60 kph and acceleration is slow.
i a new so if this has been discussed pleased ignore my lack of knowledge on previous posts.
thanks for all your help.
truck is all original with 244,000 km or 146,000 miles
360 gas
auto
4x4
regular cab, short box, sport model
truck idles fines and revs good, just when you drive, and the tranny seems suspect too

 

So you can red line the RPMs when idling if you rev it correct?

 

Does the exhaust sound like someone put an even bigger muffler on it or does it breathe free with a hollow rumble to it? If not it could be your cat is clogged. These Magnum's are known for the intake leak that puts excessive oil into the cylinders then on to the cat where it clogs like cholesterol in your arteries.

 

yes redline no issue....
no excessive smoke
good pressure on the tailpipes

 

a nice rumble
no hesitation
replaced both o2 sensors too

 

Then what I would do is start with a fuel pressure test if they turns out to be good (minimum of 48 psi and may have to take the GAUGE to with windshield and drive with it) then a compression and leak down test

 

will do thanks.....