Truck is slow at acceleration and tops out at 45mph why?

i have been reading stuff about rangers because i bought one myself and what seems to be the problem for people is the fuel filter its about 10 dollars and check your oil pressure i put some fuel line cleaner in to my gas runs a bit better so try fuel filter and check your oil pressure that could be the problem

uh... if oil pressure is related at all, You would need a new engine. anyone who reads that... Oil pressure isnt the hole to look in. in general, oil pressure is.. there, which is good, or not there, which is catastrophic there are some finer points in oil pressure issues, but it wont affect driveability that way

I have the same problem , did you get it fixed?

Mine is doing the same. Ive widdled it down to a cylinder gasket blow out about 1in. Located at the 1st cylinder. The only way to see it was to take the belt off then the alternator. Unfortunately this is a 20$ part $1500 job. Since you have to disassemble the whole top of the engine a head gasket replacement kit new cylinder head bolts and thermostat change should just be done. If there are other issues things may need to be machined.

Maybe a clogged cat. Did you test that or replace it?

Or faulty O2 sensors?