Trouble Mounting Tires With Pressure Sensors

[Pat M.]

Hello. I've got replacement sets of correct wheels, tires and tire pressure sensors for my 96, and I went to have them mounted today at a local Goodyear Tire shop. They told me they were unable to get the original style run-flats over the tire pressure sensors (the large worm-clamp style), and thus could not mount the tires.

What's the deal? Based on C4 pictures I've seen these sensors don't look bigger than they're supposed to be, and I believe the part numbers are correct.

What's the trick to mounting run-flats using first-generation tire pressure sensors?

Thanks, Patrick Moresi #45581

[Joseph T.]

Re: Trouble Mounting Tires With Pressure Sensors

Patrick
Because of the way the run flat tires are made there is no give in the sidewalls. As you know that is the reason why they work the way they do. This design has caused many problems in mounting and dismounting. There are special tire machines made to help do this. Without the proper machine it is next to impossible to change these tires. Also you need a lubricant to put on the tire bead before mounting to help it slide on the wheel. What has to happen is to start mounting the tire so that you end up with the sensor at the end of the mounting rotation. If you don't the bead drops in the well of the wheel and destroys the sensor. Also that clamp that holds the sensor is subject to damage also, hense the mounting lubricant. No doubt that this is a poor design. The new ones of today are much better.

Joe

[john daly]

Re: Trouble Mounting Tires With Pressure Sensors

Patrick,
Here's what the sevice manual has to say:

Mounting and Dismounting
Due to the unique reinforced sidewall construction of this type of tire some special servicing techniques are required. This mainly pertains to mounting and dismounting the tire from the wheel.

Caution: Inflation pressure exceeding 276 kPa (40 psi) may be required to seat the beads during mounting. To prevent serious injury, only specially trained tire technicians should mount or dismount these tires. A tire inflation safety cage and clip-on air hose must be used. A rim clamp/European style tire changer is also recommended to mount or dismount run-flat type tires.

If a "run-flat" style tire must be dismounted for non-tire related reasons such as a wheel, valve, or sensor replacement, it is recommended that the job be sublet to an authorized tire service facility if your dealership DOES NOT have qualified personnel and the necessary equipment described above.

Extreme care must be taken that the tire pressure warning sensor and O-ring inside the tire are not damaged. Some tire changing equipment companies such as Coats* and Hunter* have put together a procedure booklet for these tires.

Caution: Even when using a safety cage to seat the tire bead, do not exceed 552 kPa (80 psi). If the bead does not seat by 552 kPa (80 psi), you should deflate the tire and change the position of the tire in relation to the wheel. Use of tire lubricant is also advisable.

*We believe these sources and their equipment to be reliable. There may be additional manufacturers of such equipment. General Motors does not endorse, indicate any preference for, or assume any responsibility for the products or equipment from these firms, or for any such items which may be available from other sources.

[Pat M.]

Thanks Guys *NM*