RMM bushings splitting

[Alkoran]

Any of you ever had this? Is this normal or concerning? This RMM has approx 15K miles.

 

[BadShot]

Heat + poly + time = whoosh rear motor mount replacement bushing kits Fiesta ST 2014-2019 – whoosh motorsports

 

[Alkoran]

Heat + poly + time = whoosh rear motor mount replacement bushing kits Fiesta ST 2014-2019 – whoosh motorsports

Heat + time on barely 15k miles? Seems excessive no?

 

[BadShot]

Heat + time on barely 15k miles? Seems excessive no?

Absolutely agree that does seem soon for failure, but I'm not sure how long they usually last and I imagine driving habits have a bit to do with it also. I saw a few posts about poly mounts failing and being harsh so I went EPDM mounts. Only about 3k on mine but so far so good.

 

[TDavis]

I understand every brand has its issues but when I saw the title of this thread without even opening it I assumed it was a Whoosh.

Heat + time on barely 15k miles? Seems excessive no?

Definitely doesn't seem right. My AWR RMM is at 63k and still looks new. Thats also with a dozen track days.

 

[Alkoran]

Alright, thanks for you input guys. I'll contact Ron.

 

[Dialcaliper]

Specifically for this reason Ron sells a refurb kit with new replacement bushings. Polyurethane doesn’t like the kind of heat the RMM sees near the cat. Engine side bushing starting to round out and fail In 15-20k miles is not out of the question.

it appears the street/race spec bushings are replaced by a new version of bushing

https://whooshmotorsports.com/produ...-replacement-bushing-kits-fiesta-st-2014-2019

 

[Snrub]

I had mine fail even faster than that.

I don't necessarily like buying knock off Chinese parts, but I did buy a whole new RMM with bushings because it was cheaper shipped to the door than just buying new Whoosh bushings. I hoped they might be more durable. So far, they're holding up.

 

[grimlock212]

I assume if you buy a Whoosh RMM today it comes with the upgraded bushing? Is Whoosh still regarded as the best RMM option for a bolt on street driven Fiesta ST? When I search, Whoosh seems to be the one most people recommend.

 

[Dialcaliper]

I assume if you buy a Whoosh RMM today it comes with the upgraded bushing? Is Whoosh still regarded as the best RMM option for a bolt on street driven Fiesta ST? When I search, Whoosh seems to be the one most people recommend.

Whoosh is the good budget option and the bushings are replaceable

The Rolls Royce is Vibratechnics. Their RMM uses molded rubber bushings, which aren’t as sensitive to heat as polyurethane (but are more expensive to make especially in small quantities)

 

[Grsemky]

Whoosh is the good budget option and the bushings are replaceable

The Rolls Royce is Vibratechnics. Their RMM uses molded rubber bushings, which aren’t as sensitive to heat as polyurethane (but are more expensive to make especially in small quantities)

I'd argue this is the best budget option, I have 20k on mine with no issues... If only I could find a passenger Mount for as great as price

 

[Dialcaliper]

I'd argue this is the best budget option, I have 20k on mine with no issues... If only I could find a passenger Mount for as great as price

I’d keep an eye on it - depending on how hard and hot you run the car, the polyurethane right next to the catalyst will degrade. 25-30k is where I started noticing that the engine side bushing was rounding out a bit. You won’t necessarily see cracking until it’s much farther along

It’s not obvious at all unless you actually get your head under there, ideally idling with the A/C on and see if the engine is shaking a bit more than usual. The only thing you might notice from the cabin is that the engine actually feels smoother than it did when the RMM was new because it’s no longer fully restrained by the poly bushing

 

[Grsemky]

I’d keep an eye on it - depending on how hard and hot you run the car, the polyurethane right next to the catalyst will degrade. 25-30k is where I started noticing that the engine side bushing was rounding out a bit. You won’t necessarily see cracking until it’s much farther along

It’s not obvious at all unless you actually get your head under there, ideally idling with the A/C on and see if the engine is shaking a bit more than usual. The only thing you might notice from the cabin is that the engine actually feels smoother than it did when the RMM was new because it’s no longer fully restrained by the poly bushing

I check it out every oil change just cause it was cheap, but so far so good in the Arizona heat... We definitely idle with AC on 😂 I need to replace my engine mount it's got movement, probably going with vibra mounts and replacing the tranny side while at it