My family has owned Dodge Rams for about as long as I can remember, so I know the usual RPM at 70mph is typically right around 2000RPM. We bought this truck used from a guy that bought it at an auction, so I have zero history on it.

No matter what speed you're at the RPMs are always way over. It sounds really loud, like it's making an enormous effort just to go. If you press the O/D button the light in the dash turns on that the O/D has been turned off but there is no difference in RPMs or anything else.

It is also leaking oil (it seems like just while is running) not sure if it's related.

I haven't changed any parts on it as a need a better idea of what it could be before I start buying parts.

how much to take to a dealer to replace?

Replaced ignition switch didn't help

I am changing my transmission fluid for the first time and need to know how and how much fluid I need?

shoots codes p0252, p0251,and p1688

And when it die s it won't start for a while I changed ecm , PCM , crank shaft sensor !

Oil pressure sometime shows good and sometimes none drove it about 5 miles had no overheating problems would it be pressure sending unit or pressure regulator spring

It's starts off fine but as soon as I get on the freeway and get to 70 mph it begins to Rev very high and sticks at 3 RPMS..sometimes if I let off the gas it will shift but not always eventually it will shift gears and the rpms will drop to normal..I replaced the shift solenoid and the governor pressure solenoid ..but no change still review high
Is my professor G out there anywhere.

When I started the truck start Norma engine runs but when I try to reverse or drive truck don't move I checked all the connections but everything looks normal or on right position

1999 Dodge Ram 2500 with i6 5.9L Diesel 24 valve engine. Have replaced the ip and filter. No error codes. Power ok without a light load (i.e., 4000 lb camper trailer). Any ideas?

Cleaned the battery post and replaced the connecters as well as checked the grounds on the batteries. Still just clicks. Also tested the starter it is good

Lost all gears except 1st and rev. Attempts to move when in drive but will only move if gear lever is shifted to 1 position. Wondering what the issue could be?

Check engine light is on giving a P0222 code, replaced throttle position sensor, lift pump, and fuel filter, light is still on and giving a P0222. What else could the problem be with this code? Any advise would be greatly appreciated.

light is also out on passenger vanity mirror.