Transmissiom Problem

[hin1075w]

I have a 2000 Reflection MH. 260 Cummings engine, Allison 1000/2000 transmission. My problem is: At 60mph the rpm's are 1800. at times the rpm's will jump between 1800 and 2100.This may occure once on a trip or several times. When it happens, it may only do it a couple of times or it may go on for many miles. The problem is intermitten so I don't know when it will happen. I have had the MH at Cummings and they say the engin is ok., Allison says the trans is ok. I have changed the fluid and filter but no help. I think it may be electrical. Any suggestions?
Ken

[Randyman]

If I'm not mistaken the rpm's run off of the alternator. Could be something going on there or just a glitch. I'm sure if they have checked the motor and transmission and it is not slipping this would be the culprit. My dad had a Monaco Dynasty and when he would run the generator to power the ACs going down the road his tachometer would go goofy.