Trans slips on steep hill
 

Can the bands of the trans be tightened to prevent slippage? 190 Mercedes.

When the trans is in 4th gear only the 2 clutch packs are applied, no external adjustments.

I don't quite follow you. I would think that when on a steep hill, the trans would automatically drop down to a lower gear.

Or... do you mean that the driver must physically downshift to a lower gear in order to avoid slippage?

This is my wife's car and I just got a clarification of the situation. The trans is not slipping. The engine is (supposedly) loosing power when climbing a steep hill even though she manually downshifts when climbing the hill. I'm beginning to wonder if the slowness she experiences, may be due to her dropping the transmission down into a lower gear thus causing the vehicle to travel much slower. She said the reason she downshifts is so that the car will travel faster when going up the hill.

She needs a little more patience and maybe a physics lesson... or a more powerful car.

A 190 2.3 (was) never exactly a speed demon. One with a quarter million miles even less so. Maybe get her a 2.6? :D

Or tell her to build speed to ~90mph before hitting that hill next time.

I'd try it myself to see what the problem is.