i have a 2009 e 250 with 55thousand miles and the trans is slipping my last 3 ford vans had high millage and never had a problem

 

Is it slipping in certain gears or at all times?
Has trans ever been serviced?

 

it only slips rarely when at a stop i alwaycheck fluid levels thanks

 

You are waltzing around on me . Just kidding, There is a difference between checking the fluid level and having the trans serviced. What does your owner's manual recommend?

 

If your fluid level is where it needs to be, I would suggest to seek a good transmission shop. At 55k miles, that tranny is slipping because of a mechanical failure not because the fluid and filter have never been changed. The more you drive it that way, the more damage to clutches will occur.

 

There is a reason why we change the fluid and filter.
If the filter becomes restricted the pump can't get sufficient fluid to pressurize the system and one of the results is clutches not fully applied and slippage which results in excessive clutch disc wear and eventual destruction.

 

Yes, I agree with fluid and filter changes. However, if the filter becomes so loaded that it is restricting fluid flow enough to cause his issues in 55k miles, he's got bigger issues than just the filter. That debris came from somewhere, probably clutch material.The best advice is to seek out a good transmission shop for a consultation.