2007 Gulf Stream Sun Voyager 8368 MXG

[Rhodesia]

I have a 2007 Gulf Stream Sun voyager model 8368 Gas coach 37 feet long my question is when I'm driving up mountain pass my coach tens to almost come to a low crawl it seems even when I use my overdrive I'm not hauling anything as of yet but was going to flat tow a 2002 Jeep Liberty renegade, so what I'm asking is why do I see other motorhome gas pushers that are the same length as mine pass me up the mountains pass like it was nothing and they are towing a vehicle I have a banks system installed in mine and it works fine I have a V 10 engine because this was built on a F53 ford frame.

So if I start to tow I'm afraid that I'm not going to be able to tow the jeep up the hill if I'm crawling up it with a boat anchor. I had the Ford dealership do a complete service on the transmission and rear differential and there is nothing wrong I only have 44,000 on her. The coach drives real great So what makes my Gulf Stream different than the others that pass's me up these steep grades?