Gpribyl

When going over any bumps, a loud thump comes from the left rear. It is worse when there is someone sitting in the back on that side. It feels like that strut and spring aren't doing much and it just hits the ground. Even when you look at the car you can visually see that side sits lower than the rest. I brought it into the dealer 3 times to have them look at it and everytime they said that nothing was wrong. I had the suspension on that side replaced last year because it was making the same sound. I just cannot believe the dealership that there is nothing wrong. I am guessing they just don't want to replace it because it is covered by the warranty, but that is just my guess. They said that the sound I am hearing is the car jack in the trunk, but that is false because it makes that sound even without the jack. Does anyone else have any ideas? If I do have to replace the shocks and springs, is that very difficult? I have an 04 if that is helpful. What is the best suspension for the rear? Coilovers or just shock and spring? Should the suspension be replaced before I buy new tires? Does that have any affect on tire wear? Thanks everyone for your help.

dannobre

iTrader: (3)

If everyrhing is tight...it likely is the shock...but it could be an endlink or a bushing on one of the rear links.
Might want to take it to a suspension or alignment place that is good to have a look...they are usually better than the dealer with suspension stuff

Gpribyl

Everything seems to be tight. I checked the endlink and it is tight and intact.

Rx-elf

Its the shock absorber, if you have a bad shock absorber then the wear is gonna show most likely inside of the tire. When you have a dead absorber the tire wear will show fast.
First replace the suspension then change the tires.

Gpribyl

Is the shock absorber the same thing as the spring and strut, or a different part all together?

hellsfire

iTrader: (1)

The "shock absorber" should be the same thing as the strut you are referring too.

ShinkaEvo

iTrader: (3)

S1's rear OE shock is known to blown.
Don't get OE anymore, just get a entry level aftermarket kit to replace it.

Gpribyl

So I should get just the strut replaced? I am guessing that putting in coilovers would be overkill if all I need to do is replace the strut. Is it best to get both rears replaced? Any good places to get rather inexpensive ones that are still decent quality? Is replacing the struts a very demanding task or just an evening job?

Rx-elf

I will recommend that you change both struts.
its not a hard job takes 1-2 hours max depends if the shop has experience with 8.

Gpribyl

Is there anything visually that can help me determine that it is the strut? Has anyone replaced them yourself? Is it a do-it-yourself job or something that a mechanic should do?

DAMD

You can do it yourself. If you have some basic hand tools. If you don't have a spring compressor, most autoparts stores will rent them for free. An impact gun would be very nice to have for removing the spring as well.

Here's a good write up with pics.

https://www.rx8club.com/series-i-whe...install-87244/

DAMD

The easiest way to check the shock absorber would be to disconnect the sway bar endlink and bounce the corner that you think is bad. It should compress and extend in a controlled manner. If not it will continue to oscillate slightly after the bounce.

You should also inspect all the suspension bushings. Put the car on jack stands and use a similar procedure to inspecting wheel bearings, apply pressure to the left right then to the top bottom of wheel to check for play. If any is detected, have a friend do it while you have a look from underneath to find the source of play.

Gpribyl

Thanks DAMD for the tips and the good tutorial. After doing some investigation with a mechanic friend of mine, he said that it looks like both of the rear springs are shot, so at the very least those have to be replaced. The rear left side was the worst, but the right side was bad too. He said that while I am at it, I should also just replace the struts as well. As Rx-elf said, there was noticeable wear on the inside of the rear tires. When looked at from behind, you could see that the back tires were slightly bowed out, which is why the inside of the tire showed more wear. I would definitely need to get the springs and struts replaced before I get new tires or they are going to wear right down. I did notice that after time the car started pulling to the left more and more. Maybe due to that side having trouble. Thanks guys for all your help.

Here are the parts that he said I should get if anyone was interested.
Strut - 71123
Strut mounting kit - 906982
Rear spring - FE0228011

He said it should take us about 3 hours to get it all done.

DAMD

You may just use this as an excuse to get some performance shocks and springs. You can get some Koni yellows for the price of the OEM ones.

gquinlan

I seem to have the same problem as I've replaced the rear shocks twice in the last six months with the last set going on two weeks ago. I still hear the same thud when going over any kind of ridge or hole plus the left rear tyre has worn considerably more than any other tyre. I dont live in the USA and no Mazda tech's in country. What are the most likely solutions?

detectiveorange

You can rent a cheap spring compressor from any autoparts store like DAMD said but be extra careful. It can be a considerably dangerous/expensive job if you don't pay close attention to the spring.

Exhibit A


you should be fine though if you're smart! :P haha. Good luck! Glad you found out what your problem was