Hyperinflating tires

[Tahoe_Hybrid]

41in the rear and 40 in the front Hit 27.6MPG according to fulley

ecomodder reported I gotten 30.88mpg with the tahoe land boat(might have missed an entry ?)



Fill date Distance Fill amount Price Fuel Economy Details
2020-02-02
174 mi-280.03 km
5.634 gal (US)-4.69 gal (Imp)-21.33 L-189.87 kWh
$21.64 total
30.88 mpg (US)
37.1 mpg (Imp)
7.62 L/100 km
3.24 gal (US)/100 mi
1091.21 Wh/mi

27.6 fuelly or 30.88 ecomodder is not too bad for a 6.0 Liter v8 engine

[Galvatron1]

Originally Posted by CapriRacer

If the patched tire is leaking, that's not a good indication.

I take that back, the patched tire is holding the same exact pressure as the other 3, at 47 PSI, so I left it alone. Unfortunately, I don't have a jack. Do OHTSU tires have a tendency to bulge? I believe they are made by Falken. If it's holding pressure normally, can I rely on it at 50 PSI, or at least 35 psi or should patched tires always be replaced? Not sure how to check monthly without a jack. Thanks in advance.

[CapriRacer]

Originally Posted by Galvatron1

I take that back, the patched tire is holding the same exact pressure as the other 3, at 47 PSI, so I left it alone. Unfortunately, I don't have a jack. Do OHTSU tires have a tendency to bulge? I believe they are made by Falken. If it's holding pressure normally, can I rely on it at 50 PSI, or at least 35 psi or should patched tires always be replaced? Not sure how to check monthly without a jack. Thanks in advance.

The bulge check is to check for a separation. This is NOT tied to any particular brand. It is a typical failure mode for ALL tires.

You don't need to jack up the car to do it. Just rub your GLOVED hand around the circumference of the tire on the tread surface. Yes, you won't be able to do the part that is in contact with the ground, but there is only a small risk that a separation will be there.

The reason for the glove is to prevent damage to your hand due to sharp objects.

Also, be aware of any change in vibration. A vibration that gradually gets worse is likely a separation getting larger. The best information I have available says that it only takes a few hundred miles between the perception of a vibration caused by a separation, and a catastrophic failure - so this is something you need to act on immediately if you find it.

If you have one of those patches that don't hold higher pressure well, you will eventually know it. The patch either won't hold the pressure or the air will leak into the tire's casing causing a separation.

I think that a separation would be picked up by rubbing the tire sooner than the vibration would become apparent. So I recommend the bulge check monthly for 3 or 4 months. If after that time, you haven't felt anything, you're likely not to ever.

[Tahoe_Hybrid]

Originally Posted by CapriRacer

Also, be aware of any change in vibration. A vibration that gradually gets worse is likely a separation getting larger. The best information I have available says that it only takes a few hundred miles between the perception of a vibration caused by a separation, and a catastrophic failure - so this is something you need to act on immediately if you find it.

I had a tire with internal tread separation
12,000 miles later it still was holding up..
it would cause a violent vibration over 70mph

I just replaced them with some used Michelin Energy Saver All Season I scored for 60$ for a pair. they don't have much left but it will get me by and the 10 pounds LESS of rotating mass is noticeable...

(I put it on the drive wheels ) it still has the heavier tires in the front.





it's also better to use your hand bare just make sure no rocks are on the tread and look for the depression (flat spot) or baby bump


also the tire is not under inflated it has 40PSI (even though it looks that way)

[CapriRacer]

A couple of thoughts:

It is not uncommon for many tire shop techs to misdiagnose irregular wear as a separation. They frequently use the phrase "Slipped Belt" to describe the condition - a phrase that no self respecting tire forensic analyst uses because it doesn't describe the condition accurately.

I had a tread separation once, caused by a cut through the top belt. I first noticed a vibration and 300 miles later, it let loose. Luckily only a chunk of the tread (and top belt) came off and I was able to pull safely to the side of the road and change the tire.

Further, the belt wires were protruding, so when I felt for the bulge, I cut my hand - lesson learned!

This experience is consistent with what I know about how these failures progress and the extensive testing conducted by the company I worked for specifically designed to fail tires in this manner. It would be extremely uncommon for a tire with a tread separation to last several thousand miles before a catastrophic failure.

[Galvatron1]

Thanks CapriRacer for a better understanding & how to perform the check. I certainly don't want to cut my hand. I wonder if my winter gloves will protect my hand, whilst still allowing me to feel for separation. Or maybe feel with a folded dish towel that I could easily toss in the wash afterwards. Would the area of separation be specifically where the nail punctured the tire or could it be anywhere? I did notice some vibration briefly yesterday, but not sure if it was uneven pavement I couldn't see.

Great find on the pair of Michelin energy savers!

[CapriRacer]

Originally Posted by Galvatron1

Thanks CapriRacer for a better understanding & how to perform the check. I certainly don't want to cut my hand. I wonder if my winter gloves will protect my hand, whilst still allowing me to feel for separation. Or maybe feel with a folded dish towel that I could easily toss in the wash afterwards. Would the area of separation be specifically where the nail punctured the tire or could it be anywhere? I did notice some vibration briefly yesterday, but not sure if it was uneven pavement I couldn't see.

Great find on the pair of Michelin energy savers!

I don't think normal winter gloves would disguise a bulge, but avoid thickly padded ones.

Yes, the bilge would appear where the hole is (was - there should be a plug there as well as the patch.)

And lastly, tires tend to vibrate in the 50 to 70 mph range. That's because that is the natural resonant frequency of the suspension (There are some exceptions), and the vibration will be always be there, although it will be hard to sort out a vibration from a choppy road surface. A vibration that appears, then disappears is likely from the road.

[Tahoe_Hybrid]

Originally Posted by CapriRacer

I don't think normal winter gloves would disguise a bulge, but avoid thickly padded ones.

Yes, the bilge would appear where the hole is (was - there should be a plug there as well as the patch.)

And lastly, tires tend to vibrate in the 50 to 70 mph range. That's because that is the natural resonant frequency of the suspension (There are some exceptions), and the vibration will be always be there, although it will be hard to sort out a vibration from a choppy road surface. A vibration that appears, then disappears is likely from the road.

difference right away, even my sister noticed the difference with the other tires mine started vibrating at 70mph I hope there is some mpg gain with the better tires (less wasted energy in the forum of vibration ) as it would violently shake the whole SUV. 70-85mph range

vibration = wasted energy = drag =wasted gas =less mpg

[royanddoreen]

Wondering if Capriracer or any of you have heard of a tool where you could drive your tire onto a pad which could measure contact pressures across the thread so we could get a even footprint. this should give us max traction.
.

[CapriRacer]

Originally Posted by royanddoreen

Wondering if Capriracer or any of you have heard of a tool where you could drive your tire onto a pad which could measure contact pressures across the thread so we could get a even footprint. this should give us max traction.
.

I have not heard of such a thing. What footprint pressure machines I have seen (and I did a quick web search just now) have been for tire research and probably outside the cost range for even a tire shop.

But a good tire designer should be trying to get a footprint that has good properties over a wide range of pressures/load - like this one:



Notice how the shoulders of the tire are in contact with the road surface - even at the extremes.

Further, tire designers would try to get the footprint optimal at the placard load/pressure. So if getting max grip is the goal, a good starting point would be the placard pressure.

HOWEVER, vehicle suspensions change the orientation of the tire under cornering (and braking and accelerating). Both camber and toe can change as the suspension moves up and down and the steering wheel is turned. So this whole issue of finding the optimal pressure is going to depend on the particular vehicle involved - and most of us don't have computer models to help us sort out what the suspension is doing.