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Control arm and motor mounts need replacing?

12K views 17 replies 9 participants last post by  CO3 
#1 · (Edited)
Control arm and motor mount problems

went dealership for oil change.

they noticed lots of vibration in engine. (i thought i just needed new spark plugs since i'm pushing 125k on my Iridiums.)

passenger (top) motor mount is bad. he pushed on the seal and there was nothing there. $350 total.
he also said the rear (bottom) motor mount is damaged altho i dont see it. $250.

and the passenger front control arm is separating. I see the bushing damaged. $375

i said yes on the control arm ($200). labor is 1 1/2 hrs @ $108/hr. :(

what about the motor mounts? what happens if i dont fix it?
 
#2 ·
Motor mounts are super easy to do if you or a friend have tools and a jack.

You can buy an OEM passenger mount for .. I think it's around $70 or less from the dealership, and I'm not sure what the rear one OEM is at a dealership but probably also near $100

Labor time?

Well once you get the car in the air and the belly pan off, the passenger mount takes no more than 15 minutes (seriously... it's just 2 screws and 2 nuts).
Typically the passenger mount blows out around 60k, so I'm sure it's been dead for a long time and certainly would need replacing!

The rear one also shouldn't take long either, it's only two screws and a nut.

As for the control arm.. yeah, I've never done one of those, I'd leave that to the dealership.
 
#3 · (Edited)
Motor mounts are super easy to do if you or a friend have tools and a jack.

You can buy an OEM passenger mount for .. I think it's around $70 or less from the dealership, and I'm not sure what the rear one OEM is at a dealership but probably also near $100

Labor time?

Well once you get the car in the air and the belly pan off, the passenger mount takes no more than 15 minutes (seriously... it's just 2 screws and 2 nuts).
Typically the passenger mount blows out around 60k, so I'm sure it's been dead for a long time and certainly would need replacing!

The rear one also shouldn't take long either, it's only two screws and a nut.

As for the control arm.. yeah, I've never done one of those, I'd leave that to the dealership.
for the passenger MM, why do i need the car in the air?
it can be reached from the top of the engine.


also, what happens if i dont fix the motor mounts?
it looks more like a cushion???

so the car will just vibrate a little? kindqa like permanent rough idle even in motion?
 
#4 ·
well.. okay I guess you don't have to lol, my car is to low to fit a jack under it, but for the rear you'll probably have to have the car raised up and then need a nice big 2x4 to move the engine (and certainly will need help)

I'm not sure what worst case scenario is of them not being replaced and I'd hate to find out... and for the low cost of replacing it yourself there is no need to not replace them.

Worst case scenario would be something breaks.. and I'd hate to find out what the consequences of that are.
 
#5 ·
You can drive with blown passenger mount forever. I didn't even check mine until I got really bad wheel hop under 'sprited' driving (I was at the track). Rear mount I'm not sure, but given its design I imagine you'd start to get some clunking. If you don't drive hard you might be good. But, given that both are really easy to replace (especially with all the walk throughs on this forum) seems like not doing it would just be... well, lazy!
 
#7 · (Edited)
Steering would go to shit, your tires would get destroyed and .. actual bad things would happen lol


You SERIOUSLY shouldn't be considering not fixing these things; motor mounts and control arm bushings are MAJOR components of a car.

Seriously think about it.. motor mounts hold the motor in place.. surely that is important right..?
Control arm bushings.. even the word control arm gives you some direction that it's important on a car.. right?

You can replace all of this yourself for a few hundred bucks (although i wouldn't want to do the bushing myself), and can extend the life of your car, and if you sell it it will raise the value considerably.


That or let them deteriorate, your motor clunk out of place, torque something, twist something else, control arm bushing fall apart and the control arm itself bend out of place, you swerve off of a highway at speed taking a few people with you and .. well.. all for saving a few hundred bucks? Not anymore...
(Would that honestly happen? Probably not... but it gives a fair reason why saving a few dollars on important parts.. isn't worth it)
 
#8 ·
Not fixing those things is not an option. Start saving - Ramen Noodles is always an option if you are financially challenged.

went dealership for oil change.

they noticed lots of vibration in engine. (i thought i just needed new spark plugs since i'm pushing 125k on my Iridiums.)

passenger (top) motor mount is bad. he pushed on the seal and there was nothing there. $350 total.
he also said the rear (bottom) motor mount is damaged altho i dont see it. $250.

and the passenger front control arm is separating. I see the bushing damaged. $375

i said yes on the control arm ($200). labor is 1 1/2 hrs @ $108/hr. :(

what about the motor mounts? what happens if i dont fix it?
 
#11 ·
As for the motor mounts, I'm pretty sure you want a pretty stable connection between the engine and transmission, or bad things can happen. Anyway, if the dealer is expensive and you are not certain you want to do it yourself, you shouldn't have much difficulty finding a good, independent shop.
 
#14 ·
Losing your PMM is actually no joke. Had a friend locally who had his PMM crack after the seal breaking. The engine fell down slightly in the engine bay, changed the angle the shifter cables operated at, and caused an upshift to 5th actually force the car into 1st. Inevitably, the motor popped from an over-rev. Of course, this was during the PMM recall and he got a whole new motor and trans under the recall, but you won't be so lucky.

Mounts are wicked easy to do. Jack under the block and a total of four bolts for the PMM. The RMM you need to pop up the front end and it's all of two bolts at the back side of the block and attached to the lower subframe in the front. Takes longer to jack up the car than it takes to replace the RMM.

May as well trade it in, sell it, or total it if you would rather drive it around broken.
 
#18 ·
Aside from the catastrophic failures people are already mentioning, bad motor mounts = excessive vibration. Excessive vibration that the car is not built to handle = excessive wear. Excessive wear = more broken and worn out parts and more trips to the dealership. There is no point in trying to save money by putting it off, you will pay for it later.

Sorry for putting it so frankly/insensitive I'm on my phone and I'm trying to be brief lol. Anywho, get them fixed, motor mounts are fun to do on a lazy day.
 
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