IceyTys

05 545i and I was curious to know I am looking at buying some aftermarket wheels for my car and was wondering if it was necessary to have the TMPS on the new wheels?

will I get an error code if I dont install them on the new rims?

I plan on using my 124's for snow tires, so 3 to 4 months out of the year ill have a different set tires/wheels, so I wasnt sure if it would be worth the expense of buying a second set of tire pressure monitors or not.

what are other people doing?

thanks for your help guys.

Rudy

What date was your car built? (I think around March 2006 production, they changed from FTM to TPM.) Since your car is a 2005, you probably have FTM but just to be sure, the simplest way to figure out what you have is to look at the valve stems...

Do you currently have metal valve stems on your wheels? (not the caps, the actual stems)

If you do, then you have TPM and, if you change wheels, you'll have to mount sensors in the new wheels or you'll have a constant flat tire message (and you won't have the ability to automatically know if a tire is dangerously low.)

If your stems are not metal, then you have FTM. If you have FTM, then the new wheels will work fine -- no need to add any sensors, etc.

On either system, just be sure to re-initialize things (via iDrive settings menu) once the new wheels and tires are mounted, installed and set to the proper pressure.

JeffNNJ

So Rudy, what exactly do I need to buy in order to use my winter rims from my 06 550 on my 08?? Are all sensors the same and do they fit all rims and tires??
Thanks,
Jeff

Rudy

The simplest thing to do is get them from a dealer or from a place like Tire Rack. I think there are different sizes available since there are so many different wheel geometries...

IceyTys

Thanks for your help Rudy.

I think I have FTM then as only the caps are metal. So basically I dont need to do anything with the new rims and tires other then reinitialize the system once the new rim/tires are installed? thats great, much appreciated.

kchan

All sensors should be the same, BUT they do not fit all rims (ask me how i find out...)
My BBS rim's valve stem hole is too small to use my original valve stem from my stock wheels, so I end up buying the smaller valve stem part from tirerack. It comes in either 8mm or 11mm I think (BMW one is 11mm, the BBS is 8mm).
Now my sensors are on the rears and not the fronts (I put the sensors on when I changed my rear), but idrive still gives me a total TPMS malfunction, meaning the rears don't work by themselves. Rudy, think this is normal?
I guess I will find out when I put the front sensors back on...

Rudy

I imagine that's normal. My guess is that the system has to see data from all four sensors before it can function. Anything less than all four sensors responding will likely cause a fault or malfunction message...

lmohaxx

Hey Rudy,

So, if I have an 04 with FTM, can I add TPMs to the wheels and get the dealer to code? Is this possible?

Thanks
Chris

Rudy

I'm thinking it won't be that easy. I really don't know for sure without more research (I'll try to do some later if I can) but I have to believe there's some additional modules somewhere in the car that would have to also be installed or upgraded. I really don't think it would be worth doing because really the only benefit to having TPM is that the car will tell you which tire is low. Other than that, there's not much difference. It's possible that TPM may be a little more accurate or might warn you faster if you have a low-pressure situation (since it won't need the tire to rotate before getting a readout) but again, that's probably not worth the extra money and hassle you might run into if you try to upgrade things yourself.

Also, if you think about it, FTM can be better since you don't have to spend any additional money on sensors if you have a winter set of wheels, etc.

JeffNNJ

Big Props to Rudy for once again helping to make this site great and by giving us all valuable information. If I had not read this I would be going to the tire place next winter having no idea that I needed to provide sensors. Thank you again, my friend. YOU RULE!!