mtm

So my 2013 GL450 has both front axles with torn outer boots. I'm getting some crazy numbers quoted for axle replacement, so considering doing it myself.

Given that the car now has 93K miles, would you say it's a good idea to replace the front struts as well? I've replaced rear bags already.

Since you need to disconnect pretty much the same things for both axles and struts, seems like a good idea to replace the struts preemptively, rather than getting into the whole thing again within a year or so when the front bags blow out.

Those who have done it - how hard is it to get the axles out of the diff housing?

Does anybody have torque specs for the upper ball joint, sway bar link etc?

Thinking of getting Arnott struts and MB axles, which are expensive even at discounted $832 and $991 - do you know of any good aftermarket axles?

Finally, any tips/tricks for this job? I have the joint separator and the 36mm socket for the hub nut.

Thanks!

geniushanbiao

First you need to make sure if you have the air struts or coil spring for the front. Having air bags in the rear doesn't mean you have the air struts for the front. Take a look and make sure.

It's not difficult to get it out of diff housing. I used a 48" pry bar and didn't really apply too much force to get it out. FCPEuro sells a special tool for this purpose if you don't feel comfortable using a pry bar. You might want to get the diff seal replaced while it's out as well. The most difficult part is the collar nut on the wheel side. You will need to first hammer out the notch and this can be tricky. You can drill it out if you are discarding both the nut and the axle though. The torque of the spindle nut is huge as well. WIS says the proper procedure to torque the collar nut on 166 is first 250Nm, then loosen 180 degree, then torque to 200Nm plus 30 degree. Probably most people just give the highest torque they can give, but this requires a 3/4 drive torque wrench to complete.

Since you are basically cracking everying out, it's a good idea to get the bushings replaced. I would suggest you to get new lower control arm assembly instead of getting the 3 bushings. I did this work myself on my 2012 ML (same set up as the GL) and the front two bushings are not difficult as long as you have the bushing extractor, but the rear one is a PITA. You need a shop press to complete this job but I ended up getting the old bushing out with an angle grinder, and got the new bushing in with a 12lb hammer.

For the struts, if you are not short on money get it replaced, but it's typically not necessary. I got all 4 shocks replaced at 96k miles on my ML. I can feel a little difference but none of my family members feels any difference, which makes me question if I'm just having some illusion. As what I learned the performance of the shocks goes down every mile you drive so at this mileage it's OK to replace it, but definitely not necessary if it's not leaking or broken.

I'm not sure if there's any good rebuilt ones but I'd go with the genuine ones. You can order from an internet dealer that will save you some money. There are many internet dealers you can search around and find the best price. If the boots are just torn for not too long and it's not making any clunking noise when turning, you can also rebuild it and save some cost. There are rebuild kits available. Rebuilding CV joint is not that difficult as long as it's not damaged to a non-rebuildable point.

mtm

Thanks. Was doing pads and rotors today, so had a good look. I see what you mean about the axle nut - mine has TWO notches.

Jim Ma

Make sure to replace the Axle nuts as they are not supposed to be reused. Plus as you try to bend out the lip it will llikley tear off anyway. .

BlownV8

What X166 GL/GLS does not have air springs in the front?

geniushanbiao

You are right X166 is all air. W166 has coil spring version I mixed it lol

geniushanbiao

If you are planning to replace the axle, then you should do the brake job at the end. While they are not conflicting on the procedure, you will need to worry about contamination of the surface of the new disc when working on the axle and suspension parts. If I were you I would do the works together. Basically after removing the brake rotor and bracket and set the caliper aside, it will be much easier to work on the suspension parts as the knuckle becomes much lighter and there's more space to work with.

Also a quick note, if you are loosening the axle nut, do it with the wheel attached on the ground, unless you have an extremely powerful air impact gun.

mtm

Well, my rear pads were worn, so I did the pads and rotors on the rear and then thought what the heck and did the fronts too (had the parts sitting in the garage). No rush on the axles - since I'm replacing them rather than rebuilding, not concerned about getting dirt in.

geniushanbiao

I'm not talking about dirt. Brake is open system so dirt gets in every day. It's not a problem at all. I'm talking about oil when you happen to touch the rotor surface with your hands or gloves. So remember to spray and clean the surface of the brake rotor when you are done with the axle work. This will ensure the rotor doesn't get scored due to possible oil residual.

mtm

I know what you were talking about. I meant I don't care about dirt getting inside the CV joint, since I'm replacing the axles, not just the boots.

cetialpha5

Why not rebuild them? You can get the MB boot kits from MB. The aftermarket ones are much cheaper but there's a question of how long they will last. Mine weren't making any noise on my E350 but I replaced both outer boots. Had a mechanic do it a while ago and they're fine, no noise. If you're not up for it, you can just take them to a local shop or the dealer and have them change out the boots. You need a special tool to do the clamps at the end of the boot. At $90 for the boot, much cheaper than a new axle. I had originally put in a cheap $100 aftermarket axle in mine and it caused a vibration so I decided to get a new boot for the old axle.

https://parts.mercedesbenzofwappingersfalls.com/oem-parts/mercedes-benz-cv-joint-boot-kit-1663300085

geniushanbiao

That's why I said if the boot is not torn for too long and there's no clunking noise when turning it can be rebuilt with less cost. It's not simply the boot though you need a good disassembly and cleaning of the joint and put back with proper grease, but that saves a lot of cost.
For the clamp, I would just buy the tool. It's less than $20.

cetialpha5

I had my mechanic do it. I guess the hardest part is getting the joint apart. A lot of hammering until it finally broke free. Cleaning it wasn't that big a deal, sprayed it down with brake cleaner to get the old grease out. Examined the ***** and the joint and it looked clean and not worn out. Same deal with putting it back together, lots of hammering til it was on right. The boot kit comes with the grease packet. I just suggest a shop in case you're not up to getting the joint apart yourself. There's also places like Raxles.com who you can send it to and they will rebuild it/put the boot on. But the MB boot kit is probably a better boot than whatever material they use for their boots.