Also does anyone know where I can buy at a store? I couldn't find any on tire rack thought they might carry compact spares

 

Following some good advice on what fits/sizing earlier in this thread,I've just bought an ML spare W164 (07 model) for £75 from a breaker's yard here in the UK (a number are advertised on ebay).
It definitely fits nicely under the boot floor which shuts. I've created my own repair kit with a wrench and 5 ton bottle jack and shorter wheel nuts. Wrapped in a towel it fits neatly inside the wheel.
It will fit over the rear brakes no problem and I will check the front today (GLC 43) and report back.
On tyre longevity which some have commented on, the major issue is exposure to the sun (UV). In the case of most spares, they are stored in a benign environment and my view is that a 10 year old spare (unused) should be fine for temporary use. I still have the original spacesaver on my 1989 BMW Z1.

 

Having never run RFT's, I understand some members interest in carrying a donut spare. While I hope the RFT's get me (or my wife) home in case of a puncture, there is always the chance of a sidewall failure. And sure, there's always roadside assistance, but I have NEVER used it, so I'm more of a spare tire guy.

I agree with others about the need to be sure any spare is in good shape, but as Gobi said, donut spares are in a fairly protected environment. I actually have a 1991 Previa van with Bridgestones that are at least 15 years old. It has always been garaged and the sidewalls show no signs of dry rot and they hold air perfectly. My tire shop guy just said to keep an eye out for cracks in the sidewall. Granted, I just use it around town and would never take it on a road trip, but I'm not worried about driving it. I read a post about old spares somewhere and a tire shop guy said most of the donut spares he saw were actually in pretty good shape. The biggest problem causing failure was very low tire pressure, which allowed the bead to roll off the rim (obviously not good!) or defective valve stems. Of course the low tire pressure problem probably exists in just as many full size spares that people carry around for years, hoping they're good when they need them.

I say, if you don't need the room under the rear storage lid and you have a spare that you have checked out and it fits, go for it if it makes you feel better. Just be conservative if you ever need to use it and don't drive on it any longer than necessary to get you to a tire shop. As usual for things like this, YMMV

And yes, I understand our GLC's are very sophisticated and a donut might confuse some systems or throw off some error codes. If someone tells me (fabbrisd?) that using a donut will actually harm my car or its sensors, then a donut is out for me. Why would I want to chance that?

I'd be calling Roadside Assistance at that point!

 

Some people get these doughnut / donut spares to fit and some don't. Without going back and auditing all the posts on this topic, some GLCs have a box under the boot floor that causes problems and some don't. Also some of these donuts from other MB models see to fit better than others. I think someone had more luck with a tyre from a GLE. So the fact that one poster got it to fit and close doesn't meant that it will in all cases.

 

Agreed. I don't hate my RFT's yet, although IMHO they are a little harsher on bumps than what I'm used to. However, I've taken a couple of short trips with them and overall have no complaints. Mileage concerns I've read about are probably my biggest concern.

My interest in this thread (thanks for all the research you guys have done) is when I need to replace my original tires. By then I'll probably know exactly what I need to look for in a spare if I decide to get regular tires. Or at least what the best repair kits out there consist of.

 

So - the ML spacesaver 18 inch spare (W164 model) does fit over the front brakes of a GLC43 - but only just!
It also fits under the boot floor.
I'm happy and it will be there for emergency use only.

 

That's good to hear.
I will consider this option when/if I switch to regular tires in my glc43.
Thanks,

 

I would love to hear the advice of you experts on my particular situation, as regards a spare.

I live in California. I've had a '16 GLC for 1.5 years now. I live in the big city so I haven't worried about being far from help in case of a flat or a breakdown. But I'm planning now to start taking the car on some trips around California to parks for hiking etc. Thus I expect to be many miles away from tire dealers and Mercedes dealers.

I still have the Pirelli runflats on my car now. I only have about 8k miles on the car.

Looking through all the posts here, I'm inclined to buy a Mercedes emergency spare. I would only carry it when I'm on these trips out of town, so it doesn't matter to me if it will fit under the trunk lid or not. I'll just put it in the cargo area with a towel over it. I don't need to carry much gear, so the space taken up by the emergency spare doesn't bother me.

But it sounds as if the cost of an official spare (and tire change kit?) is pretty high -- $1500 US?. (I haven't called the dealer to ask... I'm just judging by what I've read in this forum.) For that kind of money, does it make sense in my case just to buy an actual full size tire and wheel? It seems like that would be cheaper. Once again, I don't really need the convenience of a small emergency tire. I'd only be carrying this on out of town trips.

Or should I just wing it with some tire sealant kit?

FWIW, I had my first flat with this car last week... a slow leak from a nail. Pumped up the tire with my bicycle pump and got it repaired for $20.

 

I changed to non-RFT 1st thing - bought the Mercedes "jack-tire-change-kit" with jack/wrench/Fix-A-Flat for like $80 and threw it in the truck - put the RFT's in a stack in the garage - and NEVER looked back.

Smoother - quieter - down right affordable - and fixable - I don't feel bad with no spare - I have all the other stuff I didn't have before - and I I feel great !

 

In much the same situation as the OP I bought a full sized spare wheel and tyre plus the jack. It was a LOT cheaper, and will get me a lot further than the emergency (80kms at 80km/h) if I need to use it. It takes up a lot of cargo space, and so isn't for everyone, but so does the emergency spare (not everyone can manage to fit it under the cargo area cover). People often say that RFT won't leave you stranded, but that's only partly true. They will in some situations, and IMHO there's a cost - both financial and driving quality - for their minor convenience. I've ditched them.

 

Thanks for the advice here. So, excuse the very dumb question, but where do I buy a spare wheel (in the US)? At a tire shop? Or do I need to buy that from Mercedes? I assume I can buy some sort of cheap basic wheel since I intend this to be a spare I'll carry in back when I'm on trips far away from the city.

 

Either. I bought mine from my MB dealer, as I bought one of the first GLCs out and AFAIK there weren't any other options in this country at the time, or so it seemed. That was certainly the expensive option. But since then I have purchased a set of after-market wheels in order to switch to 19". If you're in the US then TireRack have a lot of options. The key thing is getting a wheel with the correct offset, which in general will be different for after-market wheels that the OEM ones. I'd suggest getting the exact same tyre, as that will give you the greatest capacity to drive on it (distance, speed & handing).

 

MB is to cheap to include a spare and a jack for their GLC 300.
The run flats are garbage that will leave you stranded.
I would recommend you buy something other than MB.

 

I've been driving on extended mobility tires for 19 years. In that time have suffered two punctures. Both of which I continued on to the repair shop where both tires were repaired.

My current GLC with Pirelli tires have about 26,000 mlles on them. Based on remaining tread depth estimating another 8/10,000 miles life remaining.

 

If anyone has purchased this set up for their GLC 300, could you tell me how long the spare bolts are? I keep getting conflicting information from various sources and want to be sure to order the correct set. The most common size I find is M14 x 1.5 x 26/26.5 Is that correct?

Thanks in advance!

 

Since the part no for a 166 chassis is the same as the 164 (ML series), I would assume the compact spare is the same. Can anyone confirm?

Second, anyone have the part no for the shorter lug bolts required?

 

There's a photo in posts 23 & 81 that seems to show the part number.

 

 

I ordered the spare from an auto parts re-seller (junk-yard) off ebay (listing: MERCEDES ML350 ML400 ML550 18" SPARE TIRE WHEEL OEM 2012-2013-2014-2015-2016). I then ordered the spare lugs from eEuroparts.com (SKU: 18913 - Qty: 5 of 5 - Price (ea): $2.73
Item: Wheel Lug Bolt (M14x1.5x26.5mm)), picked up a scissor jack and compact extending lug wrench (with the correct size socket 17mm I think?) from Amazon and I'm all set. Everything fits the way it's supposed to and also fits under the compartment in the cargo space.

 

 

Suggest you contact your insurer and obtain a written reply. Incidentally any change to specs ate usually considered a modification and may need specific approval from the insurer. My insurer is NRMA.

 

At the time we were last discussing this, my insurer was NRMA (switched to MB Insurance for this year). NRMA said to me that they had no interest in modifications so long as the vehicle remained street legal. Have they told you something different?

 

Should have checked. Sorry. I was sure that someone had posted the part number for the shorter bolts somewhere here.

 

I think the words are clear. Street legal would mean within manufacturers specifications. All it will take is for MB to say the spare used at the time of the accident did not meet their specifications; then you will be in court fighting the insurer. Hence unless you have clearly explained to the insurer what you are doing regarding the spare and received a written acceptance from them, don't do it. Referencing a telephoe call as proof in court is fought with danger. Cheers

 

In attempting to be brief I was not entirely clear. What the NRMA actually said was that as long as the local motor vehicle registration authorities regarded the vehicle as registerable then they (non-RFT) were fine. I suspect you will give the same reply. We've discussed this here before, either in this thread or another. Here is a summary of my views.

The problem in this country is that it can be hard to get a written statement that a modification is legal, and it can be hard to get a statement that it is not legal. How does one react in this situation? People who are totally risk avoiding, and there are a few of them here, will say don't do it in such a situation.

My own view is a more pragmatic one. Some models of the GLC come fitted with non-RFT. I discussed the option of switching with my dealer when I bought the GLC and he said sure, but we suggest you wait until the first service to get some use out of the RFT, so the dealer certainly felt it was alright. Plenty of people have done it to a range of marques. There's nothing in the NRMA PDS, other than statements that modifications are covered, so long as the value insured includes them. I've had the conversation.

None of this is proof to someone totally risk-averse. I have made my enquiries and made own decision and am comfortable with it. I can see that you wouldn't be. Such it is.

p.s. One thing I was careful to do was to stick to manufacturer-specified tyre sizes, and not reduce the speed rating.