I've been trying to troubleshoot a vibration that’s coming from the middle of the car when I accelerate hard above 60mph. This year I have replaced all of the following parts:

Both front axels (shake under low speed acceleration)
Control arm bushing (these were completely gone)
Inner & outer ball joints (one of the outer ones were shot)
Tie rods (drivers side was gone so replaced both)
Struts (rears were completely shot so replaced all four with coilovers)
Lower engine mount (showed deep cracks in it)
New wheels & tires (was told by the tire shop that one of my wheel was bent and was causing the vibration)

The vibration can be felt constantly above 70mph and increases as I go faster. But the shake is more violent under heavy acceleration. I feel the vibration strongly close to my accelerator pedal and center console tower.
I have taken my car back to Les Schwab to replace my axels twice so far. Is it possible that one of them is still bad?

Is there anything else I should look into?
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Have you replaced the upper engine mount and transmission side mount?

 

well if a wheel is bent, that for sure can cause a vibration, try swapping that wheel to the back, and have everything re balanced

 

I had a vibration only at higher speeds at one point....
It was from aftermarket rims that did not have the right hubcentric rings...were off by a tiny bit..one size so about a mm or so. Right rings, no issue. If the rims are oem, this issue ofvoursr will not be a problem.
To clarify, you do not feel it when at a steady speed or cruise accleration, just hard accleration right? Then when you lift off on the throttle it goes away? Does it do it in ALL GEARS, at a given engin rpm regardless of roadspeed, or just at one gear at 60?
Anytime suspension work is done, the car NEEDS an alighnment.....this has been done since ANY SUSPENSION work listed above?

 

No, these are the only two front end parts I haven't replaced. I was told that if it was the upper mount, i should see fluid leaking and that I will have idle shakes. I checked the transmission mount when I changed the clutch last month, it showed its age (few slight cracks in the rubber) but nothing significant. Should I changes this anyway? Since I have like 170000 miles on my car.

 

My wheels have been balanced like 7 times in the last 4 months. I even bought a new set of wheels in April. At first they didn't install hub concentric rings, so I had violent shakes at all speeds. But that was taken care of once I installed the rings. They were last balanced 2 weeks ago. So I believe they should be ok for the most part. Also I dont get much vibration/shake from the steering wheel. Just the center of the car and some on my seat.

 

Yes the hub centric rings are on. There is a slight vibration on the floor over 70 mph when I'm cruising. The shake is very strong when I accelerate between 50-75. But it does go away when I lift off. I can feel the shake when I'm trying to go uphill as well at the speeds mentioned above. So far I have only noticed this on when I'm trying to accelerate on 3rd gear of above.

I took my car to alignment last month after replacing my ball joints and then last week after replacing my struts with coilovers.

 

Just a hunch....ever look at the rear brake disks?
One might be severly warped....front when when warped resting in steering wheel shake, rear can result in shake in cruise or at different speeds....would be unusual, but with all things has been done, it migh be worth to look at. Guess it could be internal to the tranny....but always look at the simple cheap stuff first! I would also move the tires around and see if you feel any changes, and besure the hubs are clean when you remount the rims.

 

Did you check the exhaust mounts, and the heat sheild

 

Yes I checked them when I did my clutch. It was all tight in there. I'm going to check the rotors to see if I can find anything there.

 

If its only under acceleration, and you're on stock motor mounts maybe there is enough play in them to allow something to contact something while the engine is moving under torque. Sorry about the incredible vagueness...I've been up for going on 18 hours now and have a few pints in me...

 

Thanks. This was going to be my next guess. I just ordered both the motor and transmission mount. I should have it before Thrusday. I'll put it on asap. Will keep you posted. Thanks.

 

I replaced the transmission and engine mount. Now 80% of my vibrations are gone. Especially the shake in the front. And my engine mount was definitely gone. Here's the video for comparison.

Worn mount.
New mount:
The new one does not have any play at all.

I know usually everyone get a thick fluid when their mounts leak. But looks like mine had thinned out and leaked away like a liquid sometime ago. Because one side of my mount looked dark. Looked like someone washed and wiped off the fluid when cleaning the engine. Probably the dealer who sold it to me.

The new mount has eliminated some of the hesitation I was experiencing in 2nd and 3rd gears. My throttle response has increased significantly.

I also learned that its best have a new torx bolt for the mount when working on the project.



Mine was really rusted and wouldn't budge.




Eventually i stripped my bolt head and had to use the Dremel to cut off the head of the bolt as you can see from the picture. If you have an impact wrench I'm sure this wouldn't be a problem.



Now I still have a shake in my seat. I have shorted it down to 3 possible causes.

1. My worn trailing arm bushing. I've been getting a knocking noise in the back every time I go over a bump. When I looked at the bushings, especially the drivers side one seems to be mostly worn. So I'm thinking of replacing this. Do I have to replace the whole bushing or can I just replace it with just the poly inserts?

2. My front right bearing. I did some figure eights in the parking lot and found my right wheel to make a growling noise when I turned left.

3. Wrapped rear break rotor. But this seems very unlikely, because I'm not feeling feeling any vibrations when i break.

 

I fixed the same issue by replacing both Front Axle assembly, i hope that if you replaced your axles you bought OEM or OEM Quality product, not some axles from Autozone, Oreilley's or any auto part store like these. They usually carry Chinese made parts like FEQ, Duralast,MasterPro, Import Direct. All these are cheap. I bought the GKN Leobro Axles from Pelican Parts, Great quality, and got rid of my vibrations under accelerations on speeds over 60mph. You dont want to have any low quality parts especially if you like to use your MCS to its fullest

 

Forget about mounts and exhaust. A vibration will come from a rotational part. I'd look closely at the wheels and or tires. If you go well above 65, does the vibration reduce? If so it's a high probability of a wheel/tire issue.

 

+1 Good info. A lot of threads I have come upon with a vibration issue was traced back to bad axles or cheaply made axles.

Definitely replace the wheel bearing and the trailing arm bushing. Since you're needing to do it, consider the Powerflex Trailing Arm Bushings HERE as their product is great for prolonged tire life, improved performance, better handling and they are more cost-effective than OEM bushings.

 

Same vibration. I can feel it bad above 60. It starts to make itself known in 4th gear, but if you pull hard enough in second you’ll just barely feel it. 6th gear at like 2600-3k is where it really gets bad at full throttle. You feel it through the pedal, your ***, even the gear **** shakes a little.

The driver side tie rod was replaced, earlier this year both axles were replaced with a single mass flywheel and clutch, and the upper pass engine mount has been replaced. Car was re-aligned and the wheels were balanced just 3 weeks ago. Nothing seems to help. My last two options are the trans side mount and the bottom engine mount right? Although I can’t find any information on either.

The shop that did the clutch, axles, and engine mount said the ENTIRE trans needs replacement because the “output shaft” is wobbling at speed on their lift. But these transmissions are supposed to be solid. Way even told me in a separate thread that he’s never heard of an R53 having vibrations from the transmission itself. So is it likely it’s the trans mount? I did a little experiment; had the car going 60 or so mph in 6th where the wobble is bad, and I just put the clutch down and played with the revs a bit. No wobble of any sort. The engine is tight and revving it doesn’t seem to do anything. But when it’s putting power to the wheels it wobbles. I don’t know if that helps to find the issue or not, but this wobble isn’t going away soon and I really need to know exactly what the problem is- I can’t just replace everything since I’m only 17 and my budget is quite small.

Anyone know how to diagnose a trans mount or bad engine mount? (Not the pass side one that everyone replaces, I already got that done.)

 

Just note that it is hard give a diagnosis without looking at the car. That being said.... Yes you are right about the transmission. The transmission is pretty solid. Mine has 370000 miles on it now

In my experience, "generally" if you are feeling vibration under acceleration, in general, it's mostly becuase the axle has gone bad.

The next best guess is you front control arms (but this vibration is usually felt mostly during braking).

You can always get a cheap new axle and replace it to see if it goes away. Though most check axles fail within a year. But it's worth a try if you are tight on a budget.

 

I have brand new OEM ones since March. The drivers side was replaced two weeks ago since there is a warranty and they can be replaced for free. But apparently my axles are good… the vibration is more from the drivers side I think. I wish there was a proper MINI mechanic in Milwaukee. I can’t seem to find any MINI wizards near me. Maybe Chicago, but I don’t know.

 

A bit of a long shot, but do you have the correct bolts for the wheels you've fitted?

 

Car is stock besides some lights and exhaust. Wheels are the standard R84 Cooper S rims with what I assume to be the same bolts since factory. They haven't been touched since the wheel balance & alingment about 2 weeks ago. I really have a feeling it's the trans mount. If it was an engine mount, wouldn't I feel it by just revving? Or wouldn't the engine feel off? It feels perfectly fine. The gearbox feels normal at lower speeds but once you get on it and hit about 55 there's just this wobble. Argh!! I wish OBD II scanners could recognise problems like this.

 

IN That case have a look at the front control arms.

 

I usually feel a bad engine mount during clutch engagement. Getting a smooth start is more difficult with the engine and trans flopping around. It probably wouldn’t be very apparent while revving with no load though. Logically, it seems like a broken trans mount would feel similar to a broken upper motor mount, but I’ve never broken my trans mount.

 

Julian - another long shot!
I'd go back & check the new driveshafts again, since that's usually the cause of the vibration you describe.
Just grab one & see if there's a tiny bit of end-to-end play - that's OK.
Then try up & down & back to front - there shouldn't be any detectable play at all.
If the car is lowered or a driveshaft is installed but not fully home are also possibilities.

 

Thank you guys for all the responses! I love to see an older thread get revived. I will check the driveshafts and the front control arms. Seems like the trans mount isn't something that breaks very often since no one I've spoken to on here has experienced it breaking, how to diagnose, or how to fix it.