I saw a movie on late night television in the early 80's and wanted to
know the name of it.  The premise was there was a group of couples
traveling in a Winnebago.  The decided to stay in a seemingly nice
town that turned out that all the residents were devil worshippers. 
Can you help me? : )

Mtleahy,

I believe the title of the movie you remember is Race with the Devil
(1975) starring Peter Fonda.

Plot Summary

"Frank and Roger and their wives take off for Colorado in a
recreational vehicle, looking forward to some skiing and dirt biking.
While camping en route, they witness a satanic ritual sacrifice, but
the local sheriff finds no evidence to support their claims and urges
them to continue on their vacation. On the way, however, they find
themselves repeatedly attacked by cult members, and they take measures
to defend themselves."
IMDB
http://www.imdb.com/title/tt0073600/plotsummary



Did you ever see the one, I think it was called "Race with the Devil"
about the family in the Winnebago that is terrorized by devil
worshipers?
ASV
http://asmallvictory.net/mt/mt-comments.cgi?entry_id=3342

Here are a few reviews from Amazon:

"An alternate title for this movie could easily be RV to Hell. Two
middle-class couples take their spankin'-new motor home on a trip to
Colorado. While camping out in Texas, the men see something they
shouldn't--a human sacrifice by Satanists who somehow manage not to
notice their Safeway- sized vehicle until the last minute. The
tourists flee from the devil worshippers, getting the monstrous RV
hung up in a stream, and so goes the rest of the movie. The local
sheriff is in league with the devil, and every town they come to is
full of pesky Satanists."


"Race The Devil is about two lame couples in a lame RV driving
cross-country to Colorado to go on vacation. Along the way they stop
in Buttcrack, Nowhere to spend the night and happen to run across the
lamest bunch of Satanists ever. The Satanists then start chasing the
RVers and wackiness ensues."


You may purchase a video copy of this film at Amazon
http://www.amazon.com/exec/obidos/tg/detail/-/630180550X/103-8989118-0440621?v=glance


Search terms:
Winnebago horror OR terror movie devil


I hope this helps!

Best regrads,
Bobbie7

This answer was right on!! You were super fast!!