5R55E slips 3rd to 4th

[cr_the_machinist]

I have a 99 Ranger 4.0 with the auto 5R55E. Just today it started slipping going from 3rd into 4th. It will shift into 4th and OD fine. The RPM's jump about 800~1000 more until the torque converter grabs. I know nothing about trannys.... anyone have any ideas on whats going on? I heard replacing the VSS can resolve this problem on some case but I never get the easy way out when it comes to auto repair. I'm thinking it may have to go into a tranny shop to get looked at.


UPDATE;

I adjusted the shift linkage cause the shift indicators were reading a little off... slipped a little bit at first then disappeared. I'm not expecting this to solve the problem but you never know. I'll find out driving to work tomorrow.

 

[Jspafford]

The shift indicator has it's own adjustment wheel under the dash.

 

[Bent Bolt]

Sounds like the valve body gaskets have failed. Common problem. Go to a dealer or a trans shop.

 

[cr_the_machinist]

Yeah, figured it was something internal. Taking her to the shop next Wednesday to see what they have to say. I'm thinking you're probably right Bend Bolt cause it only slips in that area once the trans fluid warms up.