Vibes with Gilbert

[denny]

Need some advice, I installed Gilbert's propshaft and is having weird vibration.
It vibrate a little at 2k prm and like hell over 4k rpm.

What's weird is that speed dosen't matter, If I keep it under 4k rpm I am doing over 100mph with no vibration.

I remove the propshaft just to be shure its the propshaft, and yes its the propshaft, without it no vibration.

After rotating the front u joint 180 degree, the virbation is much less. Try rotation the rear of the shaft against the transfer case, it didn't help.

The shaft is not touching anything, I follow the instruction and cut the shift linkage 1/4". Beside the shaft is painted black, I would have seen marks on the paint if it was touching anywhere.

I am thinking of putting the stock shaft back on.

Thanks

 

[leroy]

Re: Vibes with Gilbert

I imagine Gilbert's would make it right for you.

Jim

 

[JSM]

Re: Vibes with Gilbert

I am sure Gilbert will fix if is issue on there end.

What throws up a flag for me though is the RPM based. That sounds like engine to me.. I know you said you removed it for testing adn is gone, but propshaft is purely speed based.

 

[Flyin Ryan]

Re: Vibes with Gilbert

Yeah i'd think to install the stock shaft again if you have it... that way if it's still doign it then you know it's something else.. or if it's not you know it's the gilberts unbalanced or something.

 

[SY2932]

Re: Vibes with Gilbert

Here's an old post with a similar problem. Too bad the poster never followed up on how the problem was rectified.

 

[denny]

Re: Vibes with Gilbert

Thanks everyone,

Exactly the same problem
"Vibration definitely gets worse with higher rpm but not at higher vehicle speed. "
"I put the stock driveshaft back in and the vibration is gone. "

I will try to contact sy538 and see how it was fixed. I am also going ot call Gilbert today.

Thanks

 

[SY2932]

Re: Vibes with Gilbert

Once again, there was a problem associated with the Gilbert propshaft that was unresolved. As such, I will offer another possible explaination that centers around a PM that I received last month. Owner purchased a Gilbert was was having issues getting it installed. The bolt holes weren't lining up 100% and he was curious if he had to get a new flange or open up the holes with a drill or grinder. Well, it turns out that he had tried to install the propshaft BACKWARDS. That is, he installed the supplied yoke to the TRANSFER CASE instead of the FRONT DIFFERENTIAL. Obviously, removing metal from ANY rotating assembly WILL EFFECT THE BALANCE of it! Good thing he asked first before removing any metal... As such, I have supplemented this old post with another possible cause for those who are savvy enough to know how to use the seach feature.

 

[Don W.]

Re: Vibes with Gilbert

Extremely unlikely with a Gilbert but: Forget the u-joints for the moment and look at the yokes on each end of the just the shaft. They should be parallel to each other. To say it another way, if the u-joints were disassembled the holes on each end of the shaft where the u-joints go would be parallel to each other. Virtually impossible unless the spline has been taken apart for some reason but worth checking. If not parallel the shaft can vibrate because the u-joints on each end are "out of time" so-to-speak.

 

[denny]

Re: Vibes with Gilbert

Update..
I changed the trammy mount and its a lot less virbration. I know my engine mount is shot so I think my problem is bad engine and trans mounts.

I had called Gilbert and he told me that he had other customers with similar problem and its because of bad engine mount.

I got some solid mounts but I also have a block at the machine shop being worked on. So I guess the engine mount will have to wait for the new build.

Denny

 

[Flyin Ryan]

Re: Vibes with Gilbert

Good info man.. thanks for replying informing all of us with your findings