I have a 2006 Mustang, 5-speed manual transmission. Lately have had no problems accelerating from 1st to 3rd gear. Whenever I get into 4th and 5th gear the car gains speed at a very slow rate but the RPM's are going over 3,000. It sucks getting on the freeway because it takes me forever just to get up to the speed limit.

Any ideas what it could be?

 

Could be the clutch is slipping.

 

Sounds like the issue right there.

Take the car at about 15mph and get it into 4th or 5th, your RPM's will be real low.

Put you foot to the floor & one of a few things will happen.

#1 The car will slowly accelerate with your RPM's rising at the same rate as your speed. This is ok and clutch is not the issue

#2 The car stalls. This shouldn't happen but if it does clutch is not your issue

#3 Your RPM's go way up and the car accelerates very slowly or not at all. This would be a symptom of a slipping clutch.

 

+2 to these two dudes....... clutch.

 

Here's a way to tell definitely.
Get to where you are in 3rd gear and as you are driving up a
road that has an incline switch gears.
If after you switch gears you see your RPMs going up but no real gain in speed
then yes it is clutch slippage.

 

I think it's pretty unanimous here...probably the clutch

 

i don't know much about mustangs but I do know about a slipping clutch. +3