i think my rear diff is going out can this result in loss of power and bad gas mileage.....

 

Usually no. The only way for this to happen would be if it was locking/siezing up in which case you would not be "thinking" you have a dif problem, you would surely know it.


Buck

 

sounds like a tranny problem ,had the same problem with a suburban ,no power and crappy milage i had turns out the trans went out a week after i sold it. didnt ask the guy about it but thats why i got rid of it

 

It doesn't sound like anything to me at the moment...since there is a LOT of info missing.

Vehicle? Year? Motor? Auto or Manual?

There can be many different causes of poor mileage and bad performance.

And as buckw1 stated, if you had a differential problem, you'd know it