Shaking at 70+ mph

teddyrevenge

New member
So based on Wilbahs idea, it led me to think that it’s something from the front. Since literally everything has been replaced to include the hubs now, I went back to looking at the motor mounts and transmission mounts. Transmission mount is solid. Motor mounts are pretty good. When I tested them, the motor slightly raised up on the drivers side, but not enough to concern me. Then I put it in park and revved it up slowly several times. There is a distinct vibration coming between 2500 and 3000 rpms. No vibration anywhere else. I’m wondering if my harmonic balancer doesn’t like my new camshaft or if it’s just a byproduct of the can I put in it. Definitely thinking out loud here.

So question for the masses. If less than an inch of the motor rising on the passenger side enough to think it might be causing the problem? Is there a possibility that my harmonic balancer doesn’t balance as well with the cam?

I think I’m about to throw in the towel here guys and take it to a mechanics shop and pay their $100/hr fee for them to find out. I promised myself that until I make a $100/hr I would fix everything that I could. But after a whole new front end, tires, shocks and bushings, I’m running out of ideas!
 

Wilbah

Adventurer
So based on Wilbahs idea, it led me to think that it’s something from the front. Since literally everything has been replaced to include the hubs now, I went back to looking at the motor mounts and transmission mounts. Transmission mount is solid. Motor mounts are pretty good. When I tested them, the motor slightly raised up on the drivers side, but not enough to concern me. Then I put it in park and revved it up slowly several times. There is a distinct vibration coming between 2500 and 3000 rpms. No vibration anywhere else. I’m wondering if my harmonic balancer doesn’t like my new camshaft or if it’s just a byproduct of the can I put in it. Definitely thinking out loud here.

So question for the masses. If less than an inch of the motor rising on the passenger side enough to think it might be causing the problem? Is there a possibility that my harmonic balancer doesn’t balance as well with the cam?

I think I’m about to throw in the towel here guys and take it to a mechanics shop and pay their $100/hr fee for them to find out. I promised myself that until I make a $100/hr I would fix everything that I could. But after a whole new front end, tires, shocks and bushings, I’m running out of ideas!

Maybe determine the rpm the engine is at when you get the vibration and then see if you get the same when the tranny is in 2nd or 1st gear. If it's engine related only I'm thinking you should have the same vibration at that rpm no matter the speed of the vehicle. But if you don't get it at (hypothetically) 15 mph while the engine is at the same rpm that you get it when you are at 45 it would seem to be from something past the tranny in the drive train or other area. But I could be wrong.

Have you tried balancing beads or Centromatics? If it's the wheel or tire (I know you said the tires are new but some times new ones can be off or require too much weight to be good). They're cheap enough on Amazon. ($25 or so). So might be worth trying...especially if the check at the different rpm I mentioned above doesn't tell you it's engine related. I'm just not thinking it's the engine, but Lord knows I could be way off.
 
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So based on Wilbahs idea, it led me to think that it’s something from the front. Since literally everything has been replaced to include the hubs now, I went back to looking at the motor mounts and transmission mounts. Transmission mount is solid. Motor mounts are pretty good. When I tested them, the motor slightly raised up on the drivers side, but not enough to concern me. Then I put it in park and revved it up slowly several times. There is a distinct vibration coming between 2500 and 3000 rpms. No vibration anywhere else. I’m wondering if my harmonic balancer doesn’t like my new camshaft or if it’s just a byproduct of the can I put in it. Definitely thinking out loud here.

So question for the masses. If less than an inch of the motor rising on the passenger side enough to think it might be causing the problem? Is there a possibility that my harmonic balancer doesn’t balance as well with the cam?

I think I’m about to throw in the towel here guys and take it to a mechanics shop and pay their $100/hr fee for them to find out. I promised myself that until I make a $100/hr I would fix everything that I could. But after a whole new front end, tires, shocks and bushings, I’m running out of ideas!

You say vibration at 35-60, but is that only under acceleration, or also when you're coasting at those speeds? You also say it isn't noticeable when cold... The movement in the engine mount on the passenger side is worth taking care of. It's not difficult or expensive.
 

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