When ever I drive my truck and I shifts into 4th around 45 mph I shakes like the auto trans in slipping. It doesn't do it if you are acellerating but just cursing around town say trying to go 45mph it jerks. Is the trans fixing to go it has 152,000 on the stock dodge trans. If it is the trans what is a good trans to get. What would reliably hold up to maybe 350hp 750ftlbs tourque. I want to get 3k spings and differnt fuel plate. Maybe 350hp is too high. I just want to wake it up a good bit but still retain decient milage 17-18+ Do I have to high expectaions and what would be the cost of the new trans.

 

could be unbalnced tire it would do that i had the same problem

 

What RPM are you at when this happens? If you are below about 1400 RPM (locked in OD @ 45 MPH) it is normal - if you consider that normal. Mine does it too and I believe many people call it "tranny shudder". When I have to drive around that speed I hit the OD button and lock out the overdrive.

You can TRY to adjust your TPS to increase the shift point but it's not really a cure. Just don't run at that speed locked up in overdrive - keep the RPM up a little.

 

I keep my OD off until I'm at a consistant 50+ mph. This is about 2000 RPM in 3rd. When I want the OD on , I turn if back on, then right before it shifts, let off the pedal a little and it will shift smooth.