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Need new tires and want to get a bit more clearance (taller tires): questions

1603 Views 29 Replies 10 Participants Last post by  Gabor Latte
Hi. It's soon time to replace my 95 Astro tires. Presently I have the standard issue/recommended tire size of 215 /75 R15 on them. However, I've been desiring a bit more clearance on the van and've heard that taller tires is one way to accomplish this. Even an inch higher would be an appreciated improvement. But I'm wondering if any taller tires will lower the mpg (very important to me), or mess up the odometer accuracy (important too, tho' a bit less so). I also want to get tires that are decent and durable on the many rocky roads on which I take my camper-van to, like, maybe something in the better traction/high performance spectrum? I don't encounter much snow or rain in the landscapes I roam, but yeah, it's often in/out on dirt roads where many rocks abound. Oh, and also, I don't wanna spend a lot of money - my budget is around $100 a tire. Any tips and/or recommendations of size or brand are welcome. Thank you.
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Thanks for the response Will. I'd gone through several threads before posting but just went through more now. Came across your words from 2 years ago, pasted here for reference and posterity's posterity.

"Want good mileage, get a stock sized highway tire designed for that.
Good traction and reliability off-road, they have tires for that but you pay for it as they are heavier and have a higher rolling resistance.
Need better clearance, get a taller tire and pay with the MPG hit you will take.
Want good snow traction, get dedicated snow tires, but you pay by having another set of tires that will wear out quicker when not on snow.
Don't have a lot of money, get cheaper tires and pay for it by having less performance and/or having to replace them sooner.
No matter what tires you do end up with, getting a truck tire is my #1 recommendation, passenger tires just weren't made for our vans.

So then, can you briefly explain why you recommend a truck tire, what is a truck tire (initial research says they're larger/wider than car tires - so, will this affect mpg?), and potentially recommend a brand/model?
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So LT tires will give a softer ride but they are heavier and thus will weigh down the mpg and yet they can fill to a higher psi which might then lower the mpg so maybe no mpg loss in the end?

I haven't been particularly dissatisfied with the quality of the ride on the standard issue non-LT tires, although sure it's stressful when riding, even very slowly, on rocky uneven terrain to get to a boondock am always interested in upgrading my lifestyle/comfort-level (as long as it doesn't impinge much on my wallet).

Aside, would 225s, instead of 215s, give me slightly more clearance but with barely any mpg loss? And/or R16 vs R15? Even a half inch higher tire might avoid some undesirable cosmetic scrapes or bruises...
From my research I've gathered that a lift will lose me MPGs, which is a dealbreaker, on top of the fact that I was/am trying to kill two birds w/one stone regards replacing tires (need to do so anyhow) and possibly aiding clearance issues via taller tires. If I'm to lose MPGs with taller tires and/or LT tires, then I reckon I must just surrender to the same old standard issues, or, yeah, maybe a very slight bump up to 225.
"you might be stuck with what you have."

Yes, playing it conservative on this issue might suit me best right now, given limited budget, high gas prices, and not wanting to give up nary a single mpg, tho the verdict isn't in just yet on the scenario that "may help compensate for the other losses." In any case, your input is helpful, Rod, so thanks!
Very interesting/intriguing, Birdshake. What was/is the brand of your lift kit? And: are you 100% certain your mpg didn't fall even a smidgeon?
Hey guys, very sorry haven’t responded sooner to the last few posts - been lying horizontal and wicked disoriented with Covid for many days, a very nasty case of it, and am on very gradual recovery path. Glad to get your testimonies of the tune which sings of a 2 inch lift not affecting mpg! That’s good. I see a lift in my future, after I first get some new tires. Faith, glad Gabor rung your bell, haha 😀. ‘Twas a spur of the last minute idea when prompted for a user name 😊. Happy new year to all 🙏.
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Hey. Thanks a lot for chiming in! That’s a wealth of input. My high top conversion van is indeed 2WD, and I had no idea this affects lift possibilities. So, yeah, if I can’t lift, say, the oil pans, then I reckon a lift will be purposeless as the big idea is to be able to maneuver over some rougher terrains without damaging anything underneath. If that’s the bottom line, I’ll just have it suck up that fact. I’ve done a whole bunch of boondocking all over the country in the past eight months, but anytime people (online) spoke of needing good clearance, I had to sadly steer clear, but I have gotten around to many remote places. I’ve also had 4 normal car tires on there, nothing whatsoever to brag about (the most esteemed is a basic Hankoock). Still, I’ve had zero complaints about the handling, aside from the dirty rocky back roads (especially washboards) where the van shakes a fair bit and is overall stressful, but not sure how much better light truck tires would manage, and not sure I really wanna fork over upwards of $1000 to find out (vs $500 for car tires). Also, despite having a fridge, bed, and kitchenette//sink area, my load is probably relatively light (not much more than if I was carrying 3-4 passengers), so “load” is not a huge issue.

Better mpg always gets my attention. And would love even little more clearance. And a smoother ride on the rocks. But maybe I can live with what I got. Jury’s still out at this moment…
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Interesting and, yeah, complicated. Thanks again for enlightening me to a 2WD’s status in regards to a lift. Overall you might’ve saved me some or other huge headaches to the moon and back if I’d walked blind into the lift situation.
Hey. Never heard of RPO 'till now and Google told me to look in so-called glove compartment and found attached sticker there, but no G80 printed anywhere.

If I'm an expert at anything it's buying things on the cheap. Current tires bought half-used and mismatched brands and for nearly nothing. But that was 18,000 miles ago. I definitely have my radar on used tires, tho' pickings slim in remote region presently abiding. But thanks for the tips - interesting that you use bigger in the back. I thought they all had to be uniform What was/is your inspiration for doing so?


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That’s a very beautiful and good-looking old gal!

Pray tell, what’s the wisdom or reason to go bigger on back? I’m actually going to check out set of used tires tomorrow, would be good to be armed with that info. Also, didn’t see/get the sticker I last attached? Any discernible/helpful info on it regards RPO?
Thanks for that translation, Rod! In fact I’ve always been puzzled/mystified by the talk of gear ratios. Now I know what I got! And yes, custom chassis/RV upgrade probably ‘cuz this here’s a high-top conversion.
Is 3:42 pretty standard?

Again, appreciate you deciphering the ancient text 🙏.
Good to know my ratio is in the standard, nothing too exotic. Some of that info goes over my mechanically ignoramus’d mind, but in time perhaps will fully compute.
Holy mother of all loads! Now I get why you’re concerned with the weight on the wheels, etc.

Alrightee, will stick to same size all around…
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