Shifting problems

[Allen Goretski]

So I have a 2000 k3500 Chevy Silverado it has a 6.5 in it and has 250,000 miles on it. Recently I have been having a lot of problems driving on the highway it seems like when ever I get up to 65 mph the rpms want to jump up to over 2,500. And it smokes like crazy. Is there any way I can get it to shift normal.

 

[NVW]

Is it accelerating hard? If it is it is likely a PMD or IP problem.

 

[ak diesel driver]

Codes?

 

[Allen Goretski]

It accelerates good until I get to 65 then rpms jump up. It down shifts for some reason and does not stay in overdrive. And no codes.

 

[ak diesel driver]

do you have a scanner you could hook up and monitor things while you drive?

 

[WarWagon]

Sounds like it is dropping out of overdrive for some reason. I would guess transmission issue, however, enough misfires from engine problems will also limp the system and command lower gears to reduce 'lugging' an ailing engine. As said above read the codes with a scanner. The SES light is all about "Emissions" and "ENGINE" so you won't see the light come on for "transmission" failures although it will store a code.

 

[ghitch75]

check and clean your grounds.......bad grounds can make the whole truck act weird.....