Hi all, first post here.

I have a 1993 Dodge B350 RoadTrek camper van with the 318. In great shape, but the cruise control loses speed sometimes. Sometimes it holds.

Has anyone messed with the factory cruise control on these? In my mind, a vacuum leak would make the CC lose speed *all* the time, not intermittently. Which leaves (I think) only the cruise control servo...is that right? Thanks all

 

I'll bet you have a dry rotted hose that leaks part time. It will get worse and eventually quit working at all. Trace them and squeeze lightly. If one feels crumbly, that might be your culprit.

 

My 96 was doing that but the vents for the AC were also switching to defrost when the van was under load . I replaced the check valve that is close to the throttle body and shrink wrapped one vanum idle under the passenger side headlight . Fixed both issues . By the way the check valve only blew one way so ut appeared good even with a mighty vac . The mopar replacement valve has a larger diameter

 

Do you have a 2-Piece speedo cable ?
My 89 with Cruise used a 2-Piece speedo cable with a speed sensor mounted in between them.

If you have that arrangement - check your CEL Code History (key dance) for a code 15