Hate to come on here crying for help right away but my brother-in-law has a 98 XL 3.0 Automatic 4X2 with 230,000 on it and he's having transmission troubles. What his problem is that the automatic part of the trans no longer works. In other words where ever the gear selector is is what gear it's in i.e. drive is 3rd or maybe OD, 2 is 2nd and 1 is first and you can get it to shift forcibly by moving the selector but it takes some effort to do this and he's worried about hitting reverse by accident. Has anybody had this happen to them and is this an easy fix or does he see a rebuild in his near future?

 

Probably has a 4R44E transmission.

Does the speedometer work?

The trans is computer controlled and uses the speedometer(VSS sensor) to know when to shift.

I would check the wiring to the trans because of this computer control as well.
But with wiring issue or no speed sensor issue you should get a CEL(check engine light) on the dash.
So I would also check the computer, hook it up to a reader, to make sure it responding correctly.

 

Yeah I saw that his check engine light was on but he says it's been on since he got it over a year ago! He's a Dodge guy, his daughter picked out the truck.

 

From your post I would assume he is driving the truck so I would certainly hit an auto parts store that reads codes for free, and take a pencil and paper to write down ALL the codes.
Nothing worse than "I think code was 1234, but not sure", lol
After you have all the codes written down have them reset(reboot) the computer to clear all the codes, the trans may start working again, but it would only be temporary.

Codes can be general or specific, so exact code number is important.

If they can't read the codes then computer is the problem and will need to be replaced