Sirion M300 ride quality

Questions and Answers
1

Hi Guys
My M300 Sirion’s ride quality is terrible
At first I thought it was my shocks
Replaced them with Kyb Excel G, ride now is much firmer/harder, but ride quality is still shocking over uneven roads or bumps
My interior rattles have gotten much worse as well ( I think I need to strip all the panels and use anti squeak tape on all of the edges - something like this STP Bitoplast Anti-Squeak Tape - Autostyle Motorsport South Africa )

Does anyone have any luck improving the ride quality?

Thanks

2

Are your tyres old? They may be harder due to age.

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3

Hey Man,
Replaced all 4 late last year with Michelin energy saver plus
Not sure how hard the tyres are though

4

Factory sized tyres or bigger rims and lower profile tyres?

5

Factory 14 inch rims with standard 175/65r14 tyres

6

Has it always been bad, or just recently? When were bushes last replaced?

7

Once upon a time, the ride quality was semi decent
Started to deteriorate after a while, changed shocks, stabilizer links etc
Thinking of going the poly bush route hoping to take some stack out of the suspension hoping that the ride quality will improve. Gear linkage bushes are toast as well, can’t find a set locally. Busy checking at Scrap yards at the moment
With 280k mileage, I’m wondering if I should just look at replacing the car
If I do so, I will miss the power and fuel economy (under 6l/100km)

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8

Poly bushes will make the ride more harsh. If you are wanting to make the car ride more comfortably, then standard bushes are the go.

4 Likes
9

I don’t know what your standard of quality is but my m300 doesnt rattle unless you drive over a really bad road. I’ve also lowered mine by 3cm so it’s allot stiffer.

I’ve disassembled the dashboard and other plastic interior bits to fill them with sound isolating foam (which i had laying around) which reduce the road noice by allot.

If you want comfort, change back to normal bushes and the stock suspension.

10

If available, progressive coil springs would help

11

If it deteriorated “relatively” quickly and nothing you’ve done has resolved it, yeah perhaps a bushing is well and truly ‘gone’. Replacement with standard rubber bushes is likely your best option if you’re chasing a smoother ride.

2 Likes
12

NVH - noise, vibration and harshness, things manufactures work hard to reduce. As TPG said go with factory rubbers where ever they are.

You did mention “new tires” somewhat recently. What are your tire pressures?

13

Thanks All for the replies
Tyre pressure is at 2.2 bar
Factory rubbers are difficult to come by here, but I will continue to hunt around
Does anyone have part numbers for the bush set?
Might need to import from somewhere
Thanks guys

14

And

https://partsfan.com/daihatsu/jp/19e21617fa80f95eef14ef06d7faa69a/

With partsfan you can lookup the partnumbers and with amayama you can buy them. Just searching the partnumbers in Google will also yield results.

I don’t know which bushes you need to replace but most of them are pressed into the control arm or surround the swaybars. It would be easier and cheaper just to replace the control arms.

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15

Take about four 4psi out, might make a little difference. Not sure what tires your are running but experiment a bit with pressure.

16

[quote=“Mophius, post:14, topic:6011”]…most of them are pressed into the control arm or surround the swaybars. It would be easier and cheaper just to replace the control arms…[/quote]I used to remove them, through melting the old rubber and then cutting through the wall of the bushing with an acetylene torch cutter. It was quite messy. But the other alternative would be to drill out enough rubber so that a small hacksaw would fit into the hole for sawing the bushing’s wall from inside.
These bushings are dimensioned in standardized increments, for example, 40 millimeters, 45 millimeters etc… If you could match a replacement with that of another brand, you could cut the width yourself and then press in the newly modified new bushing