My 95 4runner has been running with high rpm's lately. When at higher speeds I've noticed the tach at the high 3000's ,even hitting 4000 when cruising on slight incline/decline roads...It was really noticeable the other day while driving in 85 degrees and pulling about 1000lbs (boat/trailer), the engine would whine like the rpms were going up but the tach would stay stable, then after 10 seconds the sound would diminish with no visible change on the tach and then the sound would surge again and repeat. When I stopped for gas and opened the gas cap a Huge rush of fumes and vapor came rushing out for about 6-7 secs, related?

 

That's way to many rpms for 65mph. If its an auro tranny, I wonder if its hitting overdrive, don't sound like it. That's where I would start looking. I wonder if the whine you heard was the fan clutch engaging off and on. They are supposed to do that to control heat, if that's what it was.

 

this is a 5 speed 6 cyl 3.0 , manual transmission

 

One of two things is going on: either your tachometer and cabling needs repair, or your clutch is slipping. My money is on the clutch slipping, especially if the problem is more pronounced going up hills or while towing, and even more so if performance is impacted, i.e. it doesn't pull the same loads the way it used to.

 

how many miles?