I ride my bike (bicycle not moto) regularly on the Dragon. If you haven't been there before it is really nice. (I only ride it on weekdays when traffic is light, the only people on it then are old dudes like me who are chill and friendly.) Anyway they have opened a new section of the Foothills Parkway that adds another 15 miles to it. Too many people go over the Parkway to the Dragon without exploring the new section. It is truly world-class. The bridges rival anything on the Blue Ridge Parkway from an engineering standpoint. I highly recommend it. On a bike the over and back for the whole thing is 65 miles and 8100 feet of climbing.

Enjoy your trip.

Does your AWD have a full size spare?

If so, and that spare is new/unused, you could get away with buying 3 new tires instead of 4. Match the 3 new ones to be of the same make/model/issue-date as the spare tire. Spare tire becomes a regular tire that matches the 3 new ones. Keep one of your used tires to become the spare tire.

I’ve replaced 2 front or 2 rears because of this, but all 4 is a stretch.

It does not

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who's smarter than you're? i'm!

if you have a local shop that does it, it is.

 
No spare at all? Or a donut tire as spare? Surprised if it comes with a donut, given the stress that would put on the AWD components.

All the AWD cars I've had have had doughnuts. But Subaru and Mitsubishi aren't bastions of big spenders ;)

My Fiesta ST has a full size spare! Kinda - OEM 205/40 r17, spare is 185/60 r15, which is the same OD as the OEM tires and the same size as my snow tires.

Image didn't work. What the hell are you riding around on?

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Long Chile was a silly place.

Don't your wheels turn at different speeds every time you make a turn?

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Pink? Maybe. Maybe not. You decide.

How so? My front tires are completely worm. Rears not so much. There is a massive difference in wear rates so surely after 25-40k if wear rates are different it would be affecting the diff?

What's the difference between driving with front tyres that wear faster than moving old rear tyres with less wear to front and putting new tyres on rear?

That's what the differential is there for, to allow that variation. But it's not built to have a constant differential in rotational speeds between the tires. That will damage it.

Does that apply to haldex system? Or only permanent AWD systems?

Had the same thing happen with my son's Jag. He had a nail too close to the side wall which required a new tire. But, due to the tires no longer being produced, I had to buy 4 new tires. The bright side was the shop screwed up and gave us $1000 tires for $700-ish (because the didn't have the $700-ish ones in stock).

Are you referring to the 1% difference? Not sure about Haldex - I have a Volvo right now with it but haven't played with aftermarket wheels yet. I do know it applies to Nissan/Infiniti's ATTESA system which is not permanent AWD as I had an Infiniti with AWD. I also know that it applies to BMW xDrive which is also not permanent AWD.

Personal anecdote, on my Infiniti, I drove 20,000 miles with staggered wheels and tires and the difference in rolling diameter was .73% without issue. Later on I went with same size tires on all 4 corners but smaller rolling diameter as car was slammed. I got a flat once and had to put the spare on which had a rolling diameter 5.2% bigger. Only had to go less than a mile to tire shop but got an error light because of it.

For Subarus when you put the donut on you are supposed to put in a fuse to switch to front wheel drive.

With a Haldex system, I would imagine that if the tire diameter difference is higher than X%, then the clutch would start to slip. Obviously, slipping clutches one time isn't hurting much. Slipping a clutch all the time is going to cause heat build up issues which will lead to a shorter than expected life of the system. Without some research, most manufacturers likely give some percentage of wear that is allowable.

The BMW xdrive system is a similar set up to the Haldex system, except the clutch set up is with in the transmission/transfer case and the piston is controlled to allow for the dynamic traction control system to function properly. I would assume if you turn off dynamic traction control, that a BMW with xdrive would drive ok with a mismatch. For BMW the mismatch requirement is less than 1%. My BMW doesn't have xDrive but higher rear tire wear compared to the front. If you look at BMWs in general, xdrive has lots of issues. It wouldn't surprise me that on vehicles with issues it is due to the rear tires wearing much faster than the fronts.

What I do find interesting, the Haldex system has only been out there for 20 years or so. If you break that system down vs. how a differential steering system functions and the use of the clutch and piston set up. There really are some great similarities. It is cool how something designed 100+ years ago, finally makes it into automobiles.

Automatics only.

Fixed it

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Just Triing
Triathlete since 9:56:39 AM EST Aug 20, 2006.
Be kind English is my 2nd language. My primary language is Dave it's a unique evolution of English.

put 3 plugs in it and keep going

That's cool. I used to take my kids to the shows all the time. The smell in the small arena's was awesome. We even had one come to the house for their birthday party.

Uh, no. I've been a Toyota truck guy forever; those older vehicles like 4Runners & Landcruisers are still more like the old-skool 4WD systems but w/ more sophisticated on-demand deployment so you don't have to get out to lock hubs when going off-road, etc ~ but they're not the same as the modern full-time AWD systems that are really intended for just pavement use.

Thanks for info. I just remember that truck going through anything (mainly deep snow) without having to change anything with the hubs. And remember about 10-12 years when he got a flat soon after getting new tires for it and had to get a (one) new tire from Tire Rack. .