TJ vibration at idle

mattcogdell

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I’ve read through various posts on this topic and no one has ever reported back on the issue once they fixed it.

Somewhere along the line of owning the Jeep and installing various parts, I acquired a vibration. I believe it happened after the tummy tuck but then again it’s been so long and I’ve shrugged it off that I cannot recall when it began.

The vibration it’s very noticeable at idle and goes away if you rev the rpm 200-300 rpm higher than what it idles at. The vibration continues and seems to magnify while driving.

Due to driving the Jeep more frequently now the vibration is beginning to bother my lower back. I’ll list the modifications below. To the best of my sight, the engine and trans are not contacting the body in any way nor is the exhaust contacting the frame or body.

05’ TJ Rubicon
Savvy tummy tuck
Savvy MML ( 1” blocks)
Savvy shifter
Savvy Body Lift

To my knowledge since it originates at idle, it is not drivetrain related.

Any thoughts?
 
@Midnight LJR did you ever find a cure for your idle vibrations?
I don’t believe there is a cure for the idle vibration I am experiencing from the Savvy skid because of the new Solid rubber mounts that are used.

The one I am having trouble with is I believe driveshaft related. Which I have not solved I still need to remove the front driveshaft and see if it’s the problem. I don’t get it until 65MPH or so.


The Savvy tuck is going to increase vibrations at idle quite a bit in my opinion because it has solid rubber bushings instead of the nice big soft OEM style. That is what I was trying to warn people about in my review.

If I did a lot of stop and go driving it would be quite annoying, and I would likely switch to UCF mid height with OEM mount.

Does your vibration increase as you accelerate or go away?
 
Sounds like the vibration was a result of the Savvy tummy tuck, which is something I've heard of before.
 
The more I think back on the issue the more I begin to remember it was something I noticed after the tuck. At idle if I rev it slightly it goes away. But...... the vibration will remain and continue to increase with speed. I’ve tested this by pulling the drive shafts and changing tires. So what I’m saying is, if you have driveline issues, the vibrations of those will also add to the savvy vibes.
 
I’ve also wondered, if using the brown dog ultra flex rubber mounts vs 1” blocks would make a difference. I used the savvy 1” blocks and have always been curious about the brown dog mounts.
 
I had brown dog mounts in my XJ and it vibrated WAY worse than mine does now with stock mounts and the Savvy tuck.

Did pulling the driveshafts help at all?
Manual or Automatic?
 
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I’ll also note, I do not have mml contact with the passenger frame side as some have mentioned previously.

I am happy with my 1” blocks but have wondered about the brown dogs. Did you have rubber or poly?

Pulling the shafts did not help the vibes. As I was saying earlier, pulling the shafts will only help you narrow down pinion issues, not vibe issues felt at idle.
 
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Ah got ya, I had rubber.

I think the only way you can get rid of the vibes at idle is to switch back to the OEM tranny mount.
 
Ah got ya, I had rubber.

I think the only way you can get rid of the vibes at idle is to switch back to the OEM tranny mount.
I’m afraid of that. That take extensive work and probably turn into not being worth the effort. I’ve wondered if there’s a softer durometer of rubber that could be used to reduce some of the vibration
 
Would this vibration be reduced if we were able to increase the idle rpm?
 
I’m afraid of that. That take extensive work and probably turn into not being worth the effort. I’ve wondered if there’s a softer durometer of rubber that could be used to reduce some of the vibration


Not sure, mine is not bad enough to bother me and goes away as soon as I touch the throttle.

Does yours completely go away once driving? Do you do a lot of stop and go driving?
 
I’ve read through various posts on this topic and no one has ever reported back on the issue once they fixed it.

Somewhere along the line of owning the Jeep and installing various parts, I acquired a vibration. I believe it happened after the tummy tuck but then again it’s been so long and I’ve shrugged it off that I cannot recall when it began.

The vibration it’s very noticeable at idle and goes away if you rev the rpm 200-300 rpm higher than what it idles at. The vibration continues and seems to magnify while driving.

Due to driving the Jeep more frequently now the vibration is beginning to bother my lower back. I’ll list the modifications below. To the best of my sight, the engine and trans are not contacting the body in any way nor is the exhaust contacting the frame or body.

05’ TJ Rubicon
Savvy tummy tuck
Savvy MML ( 1” blocks)
Savvy shifter
Savvy Body Lift

To my knowledge since it originates at idle, it is not drivetrain related.

Any thoughts?
May not be close,but I had a vibration at idle. Turned out to be camshaft sensor. Jeep was missing at idle,but it didn't really feel like a miss. Engine light finally came on after a while
 
Anyone resolve or find a solution to this vibration at idle post savvy tummy tuck?

I have same issue and haven't identified a solution yet.
 
I have been fighting mine for 8 years now. I fix one problem and cause another. I have had to clearance the tub, modify the motor mount lift blocks, modify the exhaust, adjust the transmission mount as it made contact with the cross bar at the bushing, ect.... I am really close, as now it only vibrates sometimes after replacing the Motor Mounts which shifted the motor up a little and now going through everything again. So something is shifting causing a vibration, as it is only vibrating sometimes, and I can't seem to find what is moving. I think the exhaust hanger mount needs to be bent a touch and maybe heating up and cooling down causes something to touch. I may just use HPTunners to bump the idle up and not let it go <800 rpm if I can't find the source but I haven't given up yet. The Motor mounts have made the biggest difference, or it caused me to shift the motor over the most.
 
I have been fighting mine for 8 years now. I fix one problem and cause another. I have had to clearance the tub, modify the motor mount lift blocks, modify the exhaust, adjust the transmission mount as it made contact with the cross bar at the bushing, ect.... I am really close, as now it only vibrates sometimes after replacing the Motor Mounts which shifted the motor up a little and now going through everything again. So something is shifting causing a vibration, as it is only vibrating sometimes, and I can't seem to find what is moving. I think the exhaust hanger mount needs to be bent a touch and maybe heating up and cooling down causes something to touch. I may just use HPTunners to bump the idle up and not let it go <800 rpm if I can't find the source but I haven't given up yet. The Motor mounts have made the biggest difference, or it caused me to shift the motor over the most.
Thanks for update. Goodluck in your endeavors.
 
Would this vibration be reduced if we were able to increase the idle rpm?
I realize this is an older topic, but I’m about to find out.

I have nasty vibes in idle when I’m Drive or Reverse holding the brake or when the AC is on. And it’s even worse when you combine those loads.

My vibes go away when I rev the engine. I’ve tried IACV, TPS, cam sensor and map sensor. I have fairly new plugs so I don’t think that’s the issue. I have no engine codes. No vibes when driving (only in idle under load).

My engine idles at 800 with 27% load (in neutral with no AC). My idle drops down when the AC is on or when it’s in drive/neutral holding the brakes.

Planning to have Ryan (from FRP) bump up my idle when it’s under load with HPtuners and his canned tune.
 
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I realize this is an older topic, but I’m about to find out.

I have nasty vibes in idle when I’m Drive or Reverse holding the brake or when the AC is on. And it’s even worse when you combine those loads.

My vibes go away when I rev the engine. I’ve tried IACV, TPS, cam sensor and map sensor. I have fairly new plugs so I don’t think that’s the issue. I have no engine codes. No vibes when driving (only in idle under load).

My engine idles at 800 with 27% load (in neutral with no AC). My idle drops down when the AC is on or when it’s in drive/neutral holding the brakes.

Planning to have Ryan (from FRP) bump up my idle when it’s under load with HPtuners and his canned tune.

Did raising your idle RPM help solve the issue?