Need help.

[Chris1973]

Feels like a bump at 30mph to 45 mph.and when I start it it rpm down then rpm a little high for a minute.problem?

 

[Fix4Dirt]

Feels like a bump at 30mph to 45 mph.and when I start it it rpm down then rpm a little high for a minute.problem?

is it commanding a shifr? v6 or v8? you said rpm down then up so is it downshifting? like from 3rd to 2nd?

 

[Chris1973]

is it commanding a shifr? v6 or v8? you said rpm down then up so is it downshifting? like from 3rd to 2nd?

V-8.when I start it rpm goes down to like 400 then jumps to like 1100 for a minute then idles perfect.and it bumps at around 35mph.dont see a rpm change and it's only really happening when it's not a gear change spot.

 

[Fix4Dirt]

V-8.when I start it rpm goes down to like 400 then jumps to like 1100 for a minute then idles perfect.and it bumps at around 35mph.dont see a rpm change and it's only really happening when it's not a gear change spot.

so the idle surges? wonder if its a vac leak that goes away as it warms up. sometimes as they warm the seals will expand and fill the gap or it will run in closed loop when cold and once it warms up open loop kicks in to adjust the mixture as needed. that sounds like it could be to me, but not sure. when i had a vac leak my 5r55e would hold the gear then click and bump shift down into. 1st at 10-15 mph, hows the fluid level in the trans?