[Jackpine]

How old are the tires on your "new" truck? You can check the age of the tires by looking for the last four digits of the DOT ID on the sidewall (next to the rim). If your tires were manufactured last year, you might see something like 4409, meaning the tires were made in the 44th week of 2009. You MAY have to look on the inside sidewall of the tire to find this number - it is not always printed on both sidewalls.

Beyond age - your question is really too complex to answer. What was the original tread depth of each tire brand compared to its current depth? That might give you some idea of how fast each is wearing.

Good guidelines for tire replacement are at 4/32" tread remaining, so you have 5/32" to go on the new tires. (Note: the replacement point used to be at 2/32" but that point gives you almost no wet traction).

My "gut" reaction would be to stay with the tires you have on the truck now. But, I'd compare the age, tread depth and rate of wear on both to make a final judgment.

I THINK your old Gryphon can be updated to work with the 2005 truck, but you'll have to talk to Bill about the costs to do so. Besides a new cable, it will require new firmware and, of course new custom programs. Maybe this is a good excuse to get a CS or CTS?

- Jack