Vibration

[Majestic]

I'm having an issue with a high speed vibration over 60mph. It's not bad, but noticeable. I was initially told by Discount Tire that I had a bent rim on the front, which they replaced, but that was not the issue. I've also noticed that when going up a hill around 30mph it also has a weird stutter/vibration. I've ordered a tube of shutter fix and will try that, but does anyone else have any ideas?

 

[Christian]

Check your engine cover/skidplate under the engine (the one you remove when performing an oil change). Any gap from being partially unfastened will cause buffeting at speed. In my case it was the same as yours (60mph) but got severe at 70mph.
So bad that I could visibly see the hood shaking. I had spent so much time looking for the cause - RoadForce wheel balancing, trying a different set of tires/wheels, shocks, etc. A matter of securing the skidplate with zip ties and all was good.

 

[Majestic]

I'll check it, but it also has a weird vibration at lower speeds when going up hill. I'm going to look at the mounts and see if they might be worn.

 

[kryptto]

hey Majestic could it be a weight on that rim? if I recall those balancers are only adjusting for certain rotations and if the weight got slapped on it could seem to come and go at exact speed ranges. I am assuming the 20" stock rims.

 

[Majestic]

hey Majestic could it be a weight on that rim? if I recall those balancers are only adjusting for certain rotations and if the weight got slapped on it could seem to come and go at exact speed ranges. I am assuming the 20" stock rims.

I don't think so. I had all four wheels rebalanced last week. It's also doing a little "chugging" going up hills at 25-30mph.

 

[SHOrod]

Have you checked the level and condition of fluid in the PTU? Do you have a scan tool that will let you monitor misfire counts in real time? It sounds like there's something that is not happy when under load.

-Rod

 

[Majestic]

Have you checked the level and condition of fluid in the PTU? Do you have a scan tool that will let you monitor misfire counts in real time? It sounds like there's something that is not happy when under load.

-Rod

PTU was serviced about 5k miles ago. Honestly, even if it's not transmission related, it's been at least 50k miles since I've changed the fluid, so that needs to be done anyway. I really should drill/tap the PTU to make servicing it easier.

 

[Majestic]

Have you checked the level and condition of fluid in the PTU? Do you have a scan tool that will let you monitor misfire counts in real time? It sounds like there's something that is not happy when under load.

-Rod

Also, like I mentioned, if I'm going up a long hill, it sort of "chugs" unless I give it more gas. Then it's fine.