Ford TPMS is set for 80 PSI rear, 55 front. THat is why the light is on.
No, a 5th tire cannot be added. Besides, its like $5 for an air gauge. Spare doesn't need checking too often.
Well I would want a unit that monitors all eight of my tires and can be selective for airing down. So much for the Ford system. At least in my case I worry about the trailer more than the van. Usually I can tell how the van drives with low tire presssure but my trailer is like a ghost behind me. I once saw a squiggly white line on the road in my mirror but the line was not on the road in front of me. Not only did I ruin the rim but the tire almost caught fire. As far as spares go, I can check the spare on the back very easy and with a on board compressor if I have to use the spare I'm going to bring it up to proper pressure anyway. But my spares are not unused tires and are rotated with the pack so once needed I would like to have the same capibilites as the rest. Just my point of view. If I didn't have a trailer I might think differently about it but an aftermarket system might be a better choice in some cases.
Dave.
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2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer
Sportsmobile (AKA Money Pit)
Linear Mode
