metroplex

I could not find a motorcraft part # for the 05-07 Mustang GT belt, and I don't recall ever seeing one on the stock GT belt other than a Ford #.

After much searching, I think I found it: JK6-1013-BA (6 ribs, 101.375" length using Motorcraft's numbering system). The price comes out the same as if I used the OEM online catalog to find a 2007 belt (the online catalog doesn't show the part #s).

A member here, Dly, is using a Gatorback 4061015 (6-ribs, 101.5" using the commercial belt numbering system), whereas someone else claimed they are using a 99.0" belt because it fits better. Ford is notorious for changing FEADs between model years, but I'm in the process of ordering some parts and would like to buy a Gatorback belt for the GT just to prevent the inevitable: a squeeling Motorcraft belt. Can anyone confirm that JK6-1013-BA is definitely the right part # or the wrong part #?

dly

I got a ford belt I brought as a spare from the Ford Dealer in the Truck.
I'll go see what the number is.

dly

Ok the spare belt I brought from the Ford Dealer is Motorcraft JK61026A 7R3Z-8620-C. The belt that broke has the numbers Motorcraft 7R3E 8620 AA >EPDM< EB. That your pick. This is for a 2007 GT/CS

metroplex

You actually broke your belt? wow!

The Rockauto catalog shows JK61013BA for the 2005-2006 Mustang GT, and Mustangs Unlimited shows JK1013BA for 05-07 Mustang GTs. Doing a search on Rockauto shows 3 JK1013's available, a AB, BA, and a AC. Supposedly, the "C" stands for "Cogged" belt.

I did a search on Yocum Ford's online parts catalog and they list the same belt (at least the price) for the 05-07 GT. I'm wondering why your dealer gave you a JK6-1026-A, which is longer than 1013. Did you notice a looser fit (easier to install) with the replacement belt, or did you just simply go with the 4061015 Gatorback right away?

dustindu4

I said I used the 99" belt because I have an UDP and Meziere pump, which both have different pulley sizes than stock.

The stock belt is 101.5"

You should be just calling the local stealership parts desk and asking them this question, they can tell you. The service manual gives part # 8620 for "front accessory drive belt" for the V6 and GT

metroplex

Thanks Dustin, that makes a lot more sense because of your underdrives and the Meziere.

dly

I never try the Ford replacement belt on. It took 3 days to get it and I found the Gatorback belt the same day I broke the stock belt after I ordered the Ford replacement. The stock belt broke after I installed the UDP and didn't replace the Alt. bolt that sticks out. It ground the belt for about a week before it let go. I'm still finding bits of that belt in the engine compartment.

metroplex

The 4061010 is too short for the 07 GT. The stock 7R3E-8620-AA measures 102.375" in length, so if the Gatorback 101.5" fits on a 07 GT/CS, then something in between 1015 and 1020 *should* work.

dustindu4

shorter is better than longer

theedge67

That's not what your girlfriend said last night when I was over there...
J/K!!

metroplex

I was barely able to slip the Gatorback 4061020 belt over the alternator pulley (last pulley before I release the tensioner). The tensioner was bottomed out and I still barely had enough leeway to slip the belt over the pulley. The stock belt was also a PITA to remove. Nonetheless I measured the stock belt and compared it with the 4061020 belt:

Stock is 7R3E-8620-AA, measured 102.375" on the outside of the belt.
Gatorback 4061020, measured 102.25" on the outside of the belt.
Gatorback 4061010, measured 101.1875" on the outside of the belt.

4061010 WILL NOT fit the 07 GT. 4061020 DOES fit. It is a tight fit now, but when the belt wears in (shoulders start wearing to fit the shoulder of the pulleys) and stretches a little, the tensioner should do its job.

From my experience, Motorcraft, Gates, Dayco, and NAPA belts aren't nearly as good as the Gatorbacks, and it's not a matter of if they squeel, it is a matter of WHEN they start to squeel.

butterbean

Just go the the Ford dealer and buy a fooking mustang belt.

Butterbean

metroplex

The Motorcrap belts are notorious for squeeling, in my experience. I bought a Gatorback, one of the best belts you can buy for any car, and it fits!

dly

MMMMM so your not bone stock anymore. Congrats on your 1st mod!!!!

metroplex

Is this considered a mod? I originally chalked it up as a maintenance item, like an oil filter, or fuel filter!

dly

Its a mod!!!! You change oil and gas Filters when they are used up, dirty, etc. You changed the fan belt to make something better!!!!

Mustang Buster

I agree, you just did a mod, ha, ha. If you had waited to replace the stock belt when it went bad, then you could chalk it up to maintenance, but since you made a pre-emptive strike to make it better, you just performed a mod.

butterbean

Anytime you fill up your tank, that is a MOD.