Shaking around 2500 rpm??

[ALayton29]

i have a 2000 ford ranger 4.0 4x4. when i get to around 2500rpm and around 40-50 mph it starts to shake and hesitate. but anything below the rpm and 40-50 mph its perfect. anything above that its perfect. it just seems to be around 2500 rpm. the truck idles good too. please help me out!

 

[RonD]

Not sure about the hesitation but vibration can come from a Fan Clutch starting to fail.
Check it by grabbing a fan blade(engine off, lol) and see if it wobbles.

 

[ALayton29]

Not sure about the hesitation but vibration can come from a Fan Clutch starting to fail.
Check it by grabbing a fan blade(engine off, lol) and see if it wobbles.

i tried that and it was tight. sometimes it shakes really bad and sometimes it doesnt at all. or maybe just a very little

 

[a31ford]

Humor me.... check the spark plugs for the dreaded "cheap gas deposits" (tan/redish deposits between the electrodes in the plugs).

I'll bet that one (or more) have a deposit in them and at a certain speed, it shorts out that (or those) plugs.

Greg

 

[ALayton29]

Humor me.... check the spark plugs for the dreaded "cheap gas deposits" (tan/redish deposits between the electrodes in the plugs).

I'll bet that one (or more) have a deposit in them and at a certain speed, it shorts out that (or those) plugs.

Greg

well that was it! i had the plugs replaced at a real small garage around the corner from me and they used about the cheapest plug and they had deposit on 3 of them! thanks!!!

 

[a31ford]

Glad you got it fixed.