2007 M35. Help locating correct PS/ alternator belt [SOLVED]

[chairmankaga]

So this is the third alternator/PS belt I've tried. All three are too long by a couple of inches. Amazon, AutoZone and Advance Auto. They all have the same part # and cross reference parts check with the OEM belt. At first I thought there might be a problem with the tensioner, but all of the new belts are longer than the old one. Can't get enough tension.
Sooo... any ideas?
Continental ContiTech PK060465, Bando 6PK1145, Gates K060465. The local dealer doesn't have the OEM belt in stock but can get one by next week, and it's also $66.

Mod edit:
I moved this discussion from the HowTo thread it was originally posted in.

[pedsemdoc]

All three are too long by a couple of inches. Amazon, AutoZone and Advance Auto. They all have the same part # and cross reference parts check with the OEM belt. At first I thought there might be a problem with the tensioner, but all of the new belts are longer than the old one. Can't get enough tension.

So when I look at Rockauto.com I see varying lengths for the alternator/power steering belt:
as long as 47 inches:
45.12 inches: http://www.rockauto.com/en/moreinfo.php ... 12&jsn=340
45.08 inches: http://www.rockauto.com/en/moreinfo.php ... 12&jsn=339
45 inches: http://www.rockauto.com/en/moreinfo.php ... 31&jsn=331

not sure why there is such a wide range...

[EdBwoy]

The Gates application says your OEM 117204P10A should translate to Gates K060450 or K060450HD.
So, a 6 rib belt approx 45 inches long if I'm deciphering it correctly. Is that approx what your OEM one is?

Converting around, means the Bando is also a 6 ribber, 114.5 millimeters long. That should work, with a half inch give or take.

For example at O'Reilly's, I'd look at both K060450 and K060445.

[pedsemdoc]

Ahhh, EdBwoy has deciphered the belt model number, like a VIN. I like looking at meh.com - they interpret the model number of the item they're selling, sometimes with hilarious assumptions...

[Sstupid]

I see Infiniti was smart enough to put the M35's AC compressor on a separate belt. That way, if the clutch on the compressor goes out, you can just cut the belt and keep driving. On the M45, you get screwed. The compressor is driven by the serpentine belt that drives everything except the alternator. That means you absolutely have to replace the compressor when the clutch goes. Ask me how I know.

[steve_c]

I just changed the belts on my M35x this past Thursday.
I went into the garbage & retrieved the old belt & the sleeve the new one came in.

For the P/S-Alt. belt, I had a Dayco 5060463. I replaced that one with a Gates K060465.
The sleeve on the Gates belt reads 13/16" X 47" OC.
It gives the dimensions in MM also; 20mm X 1195mm OC.

Interesting that you tried a K060465 and it was too long? A change from 06 to 07? Maybe X vs R/Drive?
Are you sure your tensioner bolt has full travel capabilities end to end?

This was the 2cd belt change I performed on my M.
This time around the A/C belt pulley assembly tensioner bolt was frozen solid!
I removed the tensioner assembly (3 bolts) and had to use a torch to free up the tensioner bolt from the pulley spindle.
I seem to recall years ago a few people posting about the pulley bearings going bad, and they had to buy the entire tensioner assembly from Infiniti.
I had bought an A/C tensioner bearing a few years back as a spare, but did not install it, the old one still feels smooth!

[EdBwoy]

It seems that all the VK35DE engines in the M shared the belt, pulley and bracket numbers regardless of layout.

Steve's suspicion on insufficient tensioner travel would make sense in my experience. However, Chairman said the new belts were longer than the (assumed to be already stretched) old belts, right?
... but the same Gates part number that was wrong for Mr. Chairman worked for Steve

[chairmankaga]

I got it sorted out. The 54 cm belt was actually a 56.5 cm belt. The part number on the cardboard sleeve was correct, but the belt was different. Who knows. Frustrating, nonetheless.

Ended up with these two Continental gatorback-style belts from Amazon, about $33 total.

Continental Elite 4060450 Poly-V / Serpentine Belt for power steering/alternator. For some reason the 56.4 cm belts are listed as compatible, but they are NOT. You have to get a 54 cm belt.
CRP Industries PK060465 Serpentine Belt for AC.

And despite what the FAQ says, I found the process extremely easy to do from the top, without removing the undertray. Loosen the 14mm capture nuts on the tensioners, loosen them from below, swap, tighten, run the engine for a few minutes, adjust if necessary, lock down the capture nuts to 26 ft lbs. Took me 20 minutes, start to finish, and saved me about $150 in labor.