I have an 88 W250 that has problems with the radio. The radio is getting power, as I can turn it on and change frequencies. However, the volume switch does not work when I move it up or down. What do I need to do for this?

 

Is it the stock radio? It is over 30 years old, might be time for an upgrade.

 

Yea it is. Where can I buy one and which one should I get?

 

There are lot's of aftermarket radios available. You can take your pick. A single DIN will fit just fine. Just be sure to get an installation kit and a wiring adapter. These will make installation easy and you won't butcher your wiring. Walmart, Crutchfield local audio shops can all sell you a radio. Ebay even has them. There are quite a few that don't have CD players but I like to get them with them. There are also a bunch with USB ports where you can load your music on a thumb drive.

If you want a stock radio, Ma Mopar used the same units up to around the year 2000-2001. Look around salvage yards and they don't usually pull those radios and you can get them with ape decks and, or, CD players.

 

What he said....^^