True or False? Changing tire size from stock will wreck AWD. [Archive] - Honda Element Owners Club Forum

: True or False? Changing tire size from stock will wreck AWD.


djugurba
11-22-2010, 12:59 AM
True or false?

If I use a different tire size on my E for winter tires, I will damage the AWD system - especially the differential.

Assumptions:
Summer tires are matching 215/70 16 on all 4 corners
Winter tires are matching 215/75 15 on all 4 corners
(result is winter speedo reading that is 0.6% fast, and 4 extra revs. per mile)

This difference from stock revolutions will damage the differential, and so it is essential to keep the same size tires year round, in only the size listed on the door sticker.

True or false?

Thanks!

asp
11-22-2010, 07:07 AM
Of course, there are more learned folks on this site regarding this topic, however, TTBOMN if all four tires are the same size, you cannot do any harm to the AWD system. I think the problems arise if the tires are of significantly different size (width or diameter). I am not exactly sure what 'significantly' means in this context, but I know that if your tires are worn, most tire shops will not replace a worn tire with a new one on a 4WD vehicle if the diameter of the old and new tires differs by 6 mm (1/4") or more.

Hope this helps. Good luck and don't worry. I have 225/70 16 all season michelin tires and there are no issues with interference or the 4WD and the upsize is all in accordance with Ontario Ministry of Transportation guidelines, so it is not a safety issue.

SWEET
11-22-2010, 08:05 AM
I can't give you an "expert" answer. One because I haven't changed the tire size on mine. ....BUT, if you stop and think. That is the FIRST thing (almost) everyone here does!........Just go to the TUNER section and look at what they're rolling on.

Anyway, I had to post to tell ya nice GSHP!

ramblerdan
11-22-2010, 09:43 AM
As Asp noted, all that matters is that all four tires are the same size. Who told you otherwise?

Twilightzero
11-22-2010, 11:14 AM
All above are correct. The thing that will damage the differential is tires of different sizes on the vehicle at the same time. In other words, 215/70/16 front and 205/75/16 rear or something like that. As long as they're all the same, the diff doesn't care in the least since they'll all be spinning at the same rate.

djugurba
11-22-2010, 11:52 AM
Hi folks-
Thanks for the responses. The "true" opinion on this was given to me by the manager of a shop I'd previously considered to be relatively trustworthy and knowledgeable. I think, upon reflection, that he was probably trained not to SELL and INSTALL tires other than in the size on the door jab sticker, likely for some liability concern. I suspect he took the leap that this would cause damage on his own.

I wasn't able to come up with a compelling reason that he could be correct, but it's always wise to double check... So, thanks for the confirmation.

He also was freaking out about the diff grumble at full-stop turns, and told me I had probably damaged it by running the wrong size tires. He suggested I go to the stealership for a warranty claim. I told him I had the correct fluid and was planning on changing it this weekend, and he expressed concern I would void my warranty. Maybe he needs a good therapist? So much worry!

@Sweet: Buster the dog is actually a GWP - the picture was from the shelter where we got him... And they had trimmed his beard to make him look more normal! The wirehair double coat makes him almost impervious to weather. Naturally, he loves cruising around in the E.

Twilightzero
11-22-2010, 11:55 AM
Yep the ol' diff grumble is from old diff fluid. Change it and you should be good as new :grin:

Bowzer
11-22-2010, 02:14 PM
So here's a follow up question to the OP's point: WHat about in the event of a flat and running the dinky spare? Just how much can be run on that spare when tire size has been changed? (Not to mention, it isn't the same diameter as the OEM's anyway.)

Twilightzero
11-22-2010, 02:27 PM
So here's a follow up question to the OP's point: WHat about in the event of a flat and running the dinky spare? Just how much can be run on that spare when tire size has been changed? (Not to mention, it isn't the same diameter as the OEM's anyway.)

Doesn't the spare say right on it "do not run for less than 50 miles and over x mph"?

paulj
11-22-2010, 02:48 PM
The compact spare certainly shows that a temporary difference in tire size is not harmful. It's been a while since I checked its size, but 6% smaller than stock comes to mind.

I recall some stories among CRV owners about problems caused by differences between new and old tires of the same stock size. I don't recall any E owners having problems.

Some of us have speculated that it would be better to put the compact spare on the rear (even if that required two tire changes). There are several reasons. The load on the rear wheels isn't as high. The rear ones are along-for-the-ride, normally not driven. And the RT4WD system is setup to activate when the front tires spin faster than the rear (by about 2%). So smaller tires in back are less likely to active it. Countering that reasoning is the fact that Honda does make any such recommendation.

paulj
11-22-2010, 02:56 PM
(result is winter speedo reading that is 0.6% fast, and 4 extra revs. per mile)


That 0.6% difference is small. I have 225/70/16 2%; others 235/70/16 4%.