mpx

I switched my original SC430 rims to Lexus G-Spider rims,ALSO 18'S, during course of swap, one of my sensors went bad on the RFT, I also switched to nitrogen instead of air. After a month the 2 rear tires have gone down to 30psi, and fronts to 27-28 psi. According to what they say about nitrogen, they should use about 1lb after a 6 month period.They were swapped at a reputable tire shop, im wondering if any1 can give me some ideas on how to solve this problem.
Thanks
Stan

Yes

it could be the finish on the wheels. i've seen where some people have sanded down the inside of the rim and resurfaced it to give it a better seal. nitrogen may work too. i'd try that first as it's an easier fix.

Harold57

I'd take them back to the shop that swapped them out and have them perform a leak check on them. Let them know what kind of leak rate you've experienced so they will know what type of leak to look for.

You can do it also if you have a big enough tub or body of water to submerse it in, but finding a slight leak like that may be difficult.

The TPM sensors have a history of leaking after a while. Did you have them put new kits in them (o-rings, etc.)? That was how I cured my TPM leaks.

More than likely though, it is your wheels that have the leaks. Are your new wheels new or used? If new, the shop ought to fix the problem. If used and they leak, you have a decision to make as to whether you periodically air them up or replace them altogether. (You can ask the shop if there is anything they can do for them.)

mpx

i'M BRINGING IT BACK TO THE SHOP TOMORROW, The rims are new,the tires have good thread, but arent new i will ask him about the 0 rings ..Thing is, they were not loosing psi with the stock rims i had on them. Only have the card since Feb, bought new rims from Sewell.

Harold57

In moving the TPMs from one wheel to another, they would have to deal with a new seat and if they were already formed to the old seat, they could very easily create a leak. When I got my new tires from DTC, I had them put in new sensor kits and that cost about $5 per tire, IIRC. Cheap insurance and fix. (Mine leaked prior and didn't afterwards.)

mpx

So Harold, they would have to put in new seals for all 4 tires, are they special, like a lexus part, or would it be something the tire shop should have?
btw, while doing the 4 tires one of the valves on the tpm went bad, and was replaced. I will need a new sensor for that tire. In the meantime i disabled the TPM sensors, which i dont think is a good idea with these tires, you cant really tell by looking at a bad tire that its out of air, or even low on air.

Harold57

Discount Tire had them in stock when I bought my tires. So they didn't have to retrieve them from a dealer.

I agree, especially with the run flats, you need to keep the sensors running. They are awfully cheap insurance. If your car is still under warranty, the dealer ought to replace them for free.

You might have to go to the dealer to have the new sensor programmed into the system though. There are just a handful of non-dealer service centers that can do that right now, though the industry is supposed to be training more to be able to do that. (Costco may be able to, but you'd have to check. I don't believe that many of or maybe not even any Discount Tires can do it. Sears might be another place to check.)

mpx

The senors are covered under warranty? I purchased a Lexus Pre Owned with a 6 year warranty

Harold57

Then you should be good to go. They replaced one of mine right after I bought the car. (I bought it used along with a 3 year warranty.)

mpx

I hope so, they probably wont appreciate the fact that i had the rims put on by an outside shop

jimmer!

I had the same thing happen to me after installing new alloy GS wheels and standard tires, with nitrogen.
My tire shop checked each tire and refilled.
I've had no trouble since.
So, turn it back to the installer and let them figure it out.

mpx

I went back to the shop, he took all the air out of all tires, and refilled with the nitrogen , i'll go back in 3 weeks and see how things check out. Its amazing how much better the car rides when properly inflated with the nitogen.

jimmer!

there are nitrogen naysayers, but from my ride experience, it's worth its weight in gold, especially for low profile tires.

robsvdp

Nitrogen is very light - not much gold value there

Yes

it's lighter than air actually. so it would have negative value if it were worth its weight in gold.