2006+ Mazda5 Rear Shocks Replacement

I had a blown rear shock so I went ahead and replaced it myself. Someone else posted about doing this and said it was really easy. As far as difficulty goes, it's on the level of brake pad replacement. It depends on whether you have the right tools or not. The replacement shocks I got were KYB GR-2's (Part No. 343412). You can find them online for $35 to $50 per shock.

DISCLAIMER: I am not responsible if you break something or hurt yourself while performing this procedure.

Stock shock and KYB GR-2 (silver)


Tools needed:

- 12mm deep socket (extension also recommended)
- 17mm socket
- 13mm wrench
- Floor jack
- Torque wrench (10 - 80 ft/lb torque range)
- Vice or pipe pliers

Step 1
Jack up the rear of the car as high as you can and place jack stands at the rear jack points.

Step 2
Remove the 2 rear wheels. You'll need access to the wheel well.

Step 3
Now you can see that the shock is held up top by 2 nuts (12mm) and a 17mm bolt at the bottom. Unscrew the two 12mm nuts up top with a 12mm deep socket. It's really hard to get a wrench in there because of the shape of the bracket. Your job will be a lot easier if you also have an extension so you don't have to reach all the way in there. As you start to loosen the nuts, there will be a lot of crap falling down. Make sure you protect your eyes and try not to breath in the stuff.

Notice all the shock oil that has leaked out from the blown shock.


Step 4
Uncrew the 17mm bolt at the bottom. A long socket wrench or a cheater bar will help out a lot here. I used a mallet to loosen the bolt.

This is a bad picture, but you can see the bolt. It's behind the disc brake. With the wheel off, you can reach the bolt without getting under the car.


Step 5
Take out the shock. It takes a little wiggling, but the shock can be taken out pretty easily.

Step 6
Uncrew the 13mm screw holding the dust cover/bump stop to the shock body. This step is really easy if you have a vice. To uncrew the nut, you have to hold the rod that the nut is screwed onto stationary. Otherwise, if you try to uncrew the nut, the rod and the shock body will spin with the nut. The tip of the rod has two flat faces, so if you put the whole thing in a vice, you can easily uncrew the nut.


If you don't have a vice like me, you'll have use something like pipe pliers to hold on to the rod and unscrew the nut... big PITA. This is the shock with the dust cover/bump stop off.


Step 7
Now you are ready to install the new shock. Place the old dust cover/bump stop over the new shock. My KYB's came with 12mm nuts instead of the stock 13mm. Tighten the new nut over the dust cover/bump stop.

Step 8
Place the new shock in the original rear shock location. Make sure the top and bottom mount locations are correct and thread through bottom bolt. Don't tighten this bolt just yet but make sure the bolt thread has caught and is holding the bottom of the shock in place. The new shock's rest position may not be long enough to reach to top mount location. In this case, you'll need to put the floor jack under the suspension member and raise the shock. Once the top bracket clears enough thread for the two nuts to catch, install the two 12mm nuts.

Step 9
Tighten bottom 17mm bolt (56.35-74.49 ft/lb torque from Mazda Service Manual)
Tighten top 2-12mm bolts (15.7-21.2 ft/lb torque from Mazda Service Manual)

Step 10
Put rear wheels back and lower car. Go for a test ride and enjoy your new shocks.

How's the ride quality compared to the stockers?

Thank you for posting this.

Very good write up.

Admins, please Sticky this one

Thanks
Dima

Excellent work.
Ever think of attempting the fronts?

Ride is just like stock. I will replace the fronts if they fail. Otherwise, I like the stock setup for family hauling.

Hello guys !!

I'm new in this forum group !

I just change my Rear Shock absorber yesterday and i like to thank's
you for the " How to " It was very helpful ( i never perform mechanic in a car and i just started that and i was pretty easy ) so before going to the repair shop i will think of doing it myself !!

Do you ever done the front ? it's kinda difficult because of the spring ant the aligment that we have to check !!

regards !

frdaco41,

My fronts are fine so I haven't looked into replacing them. Doing the fronts will be tough with the coilover setup. It may not be too difficult with a spring compression tool.

Excellent write up.

Since it's so easy. I am thinking of replacing with MZ3 Bilstein HD shocks the first instance of 1 shock leak/failure.

will be trying this pretty soon, just got my set of GR2's.

I just replaced the front struts with GR-2s as well. The fronts took a lot longer than the rears because you have to deal with the springs. It took me one day's time and a lot of patience.

I just replaced the two rears on our 5 with Monroe Sensatracs; the right rear had been replaced under warranty at around 30k miles, but the left was factory original and had seen better days (the car has 72k miles, accumulated in just under three years).

No comment on the Monroe shocks at this point, but I thought I'd report it is possible to replace the shocks with the rear of the car up on ramps, tires on. Unbolting the upper brackets is a bit of a struggle and it's more effort to get the old shocks out and the new ones in, since you have to compress them up and over the lower bracket, but it can be done.

The factory service book says to replace the four 'self-locking' nuts that hold the brackets in place. I didn't notice this until I started work and so I reused the old nuts. The ones on the left were ok, but the ones on the right - which apparently were reused during the previous service - are too loose. I'll probably buy new ones this week and spend another few minutes replacing them next weekend.

where the pics go?

nftyper said:

where the pics go?

Click to expand...

I can't see them, but I'm on my work computer and the IT geeks block photo servers.

Nope, pics are gone! I'm an IT geek and have a good connection at home, they're not just gone but the red X's have been supressed too!

I was able to change the shocks without the pics. But they do help alot though, hope theyre put back soon.

Rear shocks are one of the easiest things to replace in the 5, and an impact gun made it much faster.

Does 2006 and 2009 model of Mazda5 have the same rear shock absorber? Can I use also this KYB G2 shock absorber (343412) in my 2009? My rear shock is now leaking. tnx

2009 Mazda5 Rear Shocks

Is the 2006+ KYB 343412 GR-2 Shock the same for the 2009?

Thanks a10 thunder. Without the great write up and pix, I would've been really hesitant to change them myself. I went to the dealer the first time it broke (r/r), but 2 weeks ago both rear shocks were broken (the shafts were broke) and I had to go out of town. I have no idea how I broke the r/r shock in 20k miles the first time, then broke again 10k miles later. I understand NYC has potholes all over, but I'm always careful avoiding them. The only thing I can think of is, I always bump the r/r tire on the sidewalk as I park on the street.

Anyone else with 3 BROKEN shocks within 32k miles?

I've often thought we need to figure out which of the Ford family used the Mazda5 platform and try to see if there isn't a better choice than the stock Mazda5 shock. I seem to recall there was a Volvo model that was similar to our cars, I wonder what it used???