Michelin's losing air

Messages
706
Location
Boynton Beach FL.
My Hundyi has Michelin MXV 4 Plus and they keep losing air.Someone once told me if you blow them up to say 50 psi and let it out to 30 they will stop leaking. [Confused] My Firestone Firehawks on my truck never leaked.Is this a Michelin problem. [Eek!]
 
Messages
625
Location
Silver Spring, MD (USA)
Check for screws/nails. I had a tire that would very slowly bleed off pressure over the course of a week. I kept looking all over the place and couldn't find any problems. Turned out I had a small screw in the top of the tire, and I somehow would always park the car with the screw facing the road...so I never saw the problem. Finally someone pointed it out to me one day at an autocross (oops). Other things to watch out for are loose valves in the valve stem. Sometimes they need a bit of tightening. You can tell if their loose by placing your ear by the valve stem and listening for a hiss. The tires are some of the "****est" on the market though...I'd replace them regardless of issue [Smile] .
 
Messages
36,403
Location
ME
The "pump to 50 psi" thing is to reset the bead, if it ever came loose due to quite low pressure in the tire. I had a snow tire on its own rim that had lost most of its air over the summer. RE-aired it to 32 when it went on the car, it leaked down over a week. Pumped it up to 35-40 and it held. [Smile] I agree with the previous poster about leaky valve stems too.
 

Kestas

Staff member
Messages
13,942
Location
The Motor City
Overpressure the tire to maybe 50 psi and throw some soapy water on it. You should be able to find any leak that way. Common causes for slow leaks are metal shrapnel in the tire or rusty rim beads.
 
Messages
250
Location
WV
There are a couple other causes: 1.) Leaking through the rim. Some wheel manufacturers had rims that let air pass through them slowly through pores I think it was. (Chevy has this problem quite a bit and has a "coating" kit out to fix the problem) 2.) Rust, mud, debris, dirt around your seating area (bead). This has happened to my Mom's blazer before. Just some crud around the bead and it leaked very slowly. Just cleaned the bead off good and put some tire stuff on there and it seated right back fine
 

dropitby

Thread starter
Messages
706
Location
Boynton Beach FL.
I agree with all of you and will take it back to the dealer [Duh!] and have them break the tires down get out the wire brush and reinstall.I will suggest they inflate them higher but it may not sink in with them. [Roll Eyes] Since these are the dealer tires no telling what they have been through.
 
Messages
44
Location
Ann Arbor, Michigan
As someone who currently does tires for a living I must say you guys are pretty accurate so far. I'll just add one thing; a "rim leak" (what Seth_TJ suggested) is not a problem associated with just one manufacturer. It happens to all of them, particularly with aluminum wheels. Aluminum will corrode exactly where the tire bead seats. Many people will immediately counter with "aluminum doesn't rust".. well, you're correct. It doesn't. But corrosion isn't limited to just rust [Smile] Most aluminum wheels come from the factory coated in a kind of clearcoat, similar to what's used to cover the base coat of your car's paint. It gives it that nice glossy look to it. If it is compromised it makes corrosion much easier. Particularly if a careless tire technician decides to use a wheel weight that has no aluma-guard coating on it (some wheels have a small lip to hammer on a wheel weight. If your local tire shop doesn't have a good aluminum weight to fit it, they may very well just slap on an uncoated lead weight intended for steel wheels only. This is bad, as wheel weights often times take off the clear coat when hammered on. And without the aluma-guard this can be big trouble. Aluminum does not get along well with other metals. That's where most of the corrosion comes from. Think of it as the same kind of corrosion you may get on your battery terminals--caused by the transfer of electrons between two metals). Best thing to do is goto a trusted tire shop local to you and ask for a flat repair. If they can't find a leak in the tire itself it most likely is a bad valve stem or a rim leak. If you have aluminum wheels, ask for it to be buffed and bead-sealed (when you buff the corrosion off, there will be no clearcoat left. The bead-sealer, basically a liquid rubber, can take its place in that area and can at least provide some sort of buffer for the wheel to slow down the now inevitable corrosion). Aluminum wheels also corrode from the hub. The hub they rest on is typically made of iron or steel, which causes aluminum to corrode as well. I have seen wheels where the corrosion had spread to the front side of the wheel--UNDER the clearcoat. The clear was still there! Steel wheels typically seal much better for a longer time. But they still can rust, especially if you live in my area where there's a lot of moisture year-round and we put salt on the roads for the winter to melt ice and snow. Once a steel wheel rusts there isn't much you can do but bead-seal the crap out of it and pray. You can try to grind the rust off all you want, but the wheel will remain pitted. Trust me, I've tried. Other than that extended explanation, everything has already been covered by others (in a much shorter and sweeter way. I tend to blabber on a little too long sometimes). Just one more thing; tires very rarely leak because of a manufacture defect. And Michelin is a top quality manufacturer (in my book it is THE top, but there will always be disputes about that).
 
Messages
1,139
Location
USA
How can you tell if a wheel weight has an "aluma-guard" coating on it? I had my tires replaced at NTB and they did scratch up the OEM "alloy" wheel where the weights were and where the new ones are. What can I do about the damage, or is it considered standard wear? I keep thinking that my tires are losing air, but I can't figure out why. This thread is great.
 
Messages
44
Location
Ann Arbor, Michigan
quote:
Originally posted by seotaji: How can you tell if a wheel weight has an "aluma-guard" coating on it? I had my tires replaced at NTB and they did scratch up the OEM "alloy" wheel where the weights were and where the new ones are. What can I do about the damage, or is it considered standard wear? I keep thinking that my tires are losing air, but I can't figure out why. This thread is great.
The weight will have a similar color to most painted-aluminum wheels. A kind of grey/silver color (it's basically a wheel weight with paint on it). Ones without it are just bare lead. On a different note, the shop I am currently working at is a defunct NTB which Belle Tire bought. Just thought that was interesting [Smile] And you really can't do much about the damage, unfortunately. One thing you can do, as a preventative measure, is if you ever decide to get new/aftermarket wheels (or new vehicle) ask your tire shop to only use "sticky-weights" or "tape-a-weights." They are weights with an adhesive tape on the backside. They tyically get applied to your wheel out of sight (behind the spokes). There are some rims that can only be balanced with tape a weights. They don't have a lip where regular weights can be hammered onto. Unfortunately, it is inevitable that removing and replacing your typical weights will take off the clearcoat and sometimes some aluminum from your wheel as well. It normally isn't very visible unless you inspect the lip where the wheel weights are/were. There are some tires that are designed to overlap that lip on wheels so it doesn't appear to portrude out from the wheel/tire assembly. At the very least it gives the unprotected aluminum some protection from the weather... and it also covers up the part of the wheel that normally gets scratched and scored up from wheel weight installation and removal (Goodyear's Assurance TripleTreds come to mind... I believe BFG's classic All Terrain T/As have it as well.. .along with G-Force T/As.... mostly higher-end, expensive tires have them... not all either, just some.. some do call it "Rim Guard" or something along those lines as well.) I think I've been doing this for too long... heheh [Big Grin]
 

ALS

Messages
1,862
Location
Pittsburgh
I run MXV's on my Volvo alloy rims and don't have a problem with air loss. Sure they drop about 2 to 3 psi over 3 to 4 months but all tires will lose some air. On the other hand my Sister has a Eldorado and it's the rims that are the problem. She had to check the tire pressure every week before they started to glue the tire on. Dealer even told her that they (Rims) all do it. The dealer Glue's the bead of the tire to the rim. It has decreased the air loss to a tolorable level.
 
Top