I got 40K miles on my 07 FX35, one morning last week, I hear chirping when I started the car. So I went and got Gatorback belts from Autozone to replace them. The belt sizes for 07 FX35 came up on their system as: 4060465 Alt,P/S and 4040372 A/C.
So I went to install it, the A/C belt is correct, but the Alternator/Power Steering belt is WAY OFF. I bottomed out the tensioner and it's still lose.
OEM alt, P/S belt = 6PK1148, that's 45.1969 inches
Gatorback = 6PK1180, that's 46.4567 inches
The Gatorback is 1.2598 inch bigger. Needless to say, I was pissed. Then I went on Gatorback's website, and found out that they don't even make a 6PK1148 belt. Closest thing to it would be 4060450/6PK1145.
6PK1145 = 45.0787 inches
OEM 6PK1148 = 45.1969 inches
It will be .1182 inch smaller, but I think the tensioner can handle that.
So I go back to the Autozone to return the belt that didn't fit and asked for the 4060450/6PK1145 in Gatorback. Guess what? They don't stock it! Special order only, $18.99.
So for those that are planning to change your belts with non-OEM belts.. Here are some info that might come in handy, so that you don't have to jump through hoops like me..
OEM: Alt, P/S belt = 6PK1148, 45.1969 inches
A/C belt = 4PK945, 37.2047 inches
Gatorback: Alt, P/S belt = 6PK1145, 45.0787 inches (best possible match)
A/C belt = 4PK0945, 37.2047 inches (fitment/installation confirmed match)
**Based on a STOCK 2007 FX35 4WD**