Hey guys, I have done tons of searching but come up with not really the answer I'm looking for.
I want to replace the S/C belt on my car. It has been in for just over a year and is starting to look pretty beat up and cracked. I pulled my parts list to find the OEM part number 88960481. I called up my parts guy at the dealer and my discount price is $197.72. I'm not going to pay that much for a belt since I only paid $1500 for the kit.
When installing the kit I think I remember the belt being a gatorback belt but not sure. In other posts that I have read is that it's part # 4100729 and reference links for you below.
http://www.coolparts.com/products/Gatorback_Poly_V_Belts-87195-0.html
http://www.goodyearep.com/productsdetail.aspx?id=3128
This is a 10 rib belt as I read in other posts with people just cutting them in half. Does anyone have a picture of the OEM Belt that came with there kits on there fresh install with the part number on it? My numbers are all worn off. Why would GM use a 10 rib belt and cut it in half? Wouldnt a 5 rib OEM be stronger?
If someone is doing a fresh install of the 2.4L S/C kit and hasnt put on there belt yet can ya grab a picture? My numbers are all worn off.
Here is another link for reference.
http://www.j-body.org/forums/read.php?f=40&i=81730&t=81686#81730
Any help would be appriciated.
4100729
That's what I have on the 2.6" pulley. It's super tight. If you have the stock pulley there's no way you'll be able to get it on.
2001 Olds Alero (LD9)
636 whp / 543 ft-lb
@turboalero
I remember Wade Jarvis had a post of recommended belt sizes with different m45 pullies, Ill try and find it.
Im running the stock pulley on my S/C. Just would like to know the OEM one that came with the kit. Like I mentioned my numbers are worn off.
The OEM one is a 10 rib Gatorback cut in half, you can get it at AutoZone. I forget the part number though but as posted above Wade had a list of them.
And yeah, $200 for a serpentine belt is ridiculous. Someone should call GM and tell them about that.
2001 Olds Alero (LD9)
636 whp / 543 ft-lb
@turboalero
I looked under the hood tonight and I seen a tiny bit of a faded label stating 4100729 goodyear gatorback. Then another number 10pk1851 what ever that means. So it must be true that Gm cut the belts and sold them in the kits like that.
Since that's the belt thats was on there and was sold with the kit. That is the belt that will be going back on. Mine is starting to fall apart upon closer inspection tonight.
I just checked the goodyear site above and the 10pk1851 doesnt match up with the information below. Maybe I misread the 1 for a 0. Ill have to take another look.
PART NUMBER
4100729
METRIC PART NO.
10PK1850
NO RIBS
10
EFFECTIVE LENGTH
72.938
OUTSIDE LENGTH
73.688
As for the stock belt either you pay the outragous price GM charges because a 5 rib in that size is unheard of or you buy the 10 rib slice it in 2 and use half of it. GM is the only place I know you can get the belt that came with the kit. You say the belt that came with your kit new from GM had a 10PK part number than maybe GM did start cutting 10 ribs in two. I wonder what they usesd. I did mine with a utility knife and you could tell it was a cut belt even though I tried to be perfect about cutting it.
Remember in belts the last three numbers usually represent length. So the last 3 of 729 would be 72.9" length. If you see ssomething that says 5PK or 10PK that is in reference to the number of ribs 5PK for a 5 rib and 10PK for a 10rib
The Goodyear Gatorback 4100729 will fit a 2.8 This is the stock size belt.
The Goodyear Gatorback 4100729 will fit a 2.7 too
The Goodyear Gatorback 4100722 should fit a 2.6 Alot of places this part number crosses to the gates number below so make sure this is the belt you get.
The Gates Micro V K050720 wil fit a 2.5 I know because it is what I am using and it fits perfectly. The Goodyear Gatorback 4100722 will fit but not as snug as the Gates so the gates is preferred.
And for some resason I can not seem to find the other post that contained this info.
Edited 1 time(s). Last edited Wednesday, November 05, 2008 8:02 PM
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[ion wrote: C2]4100729
That's what I have on the 2.6" pulley. It's super tight. If you have the stock pulley there's no way you'll be able to get it on.
From my searching the Goodyear Gatorback 4100729 is stock size and 72.9" is stock length which makes sense to me.
I am betting you actually have the Goodyear Gatorback 4100722 on your car with the 2.6. Can you please double check what belt is on your car.
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NeoJuice wrote:I just checked the goodyear site above and the 10pk1851 doesnt match up with the information below. Maybe I misread the 1 for a 0. Ill have to take another look.
PART NUMBER
4100729
METRIC PART NO.
10PK1850
NO RIBS
10
EFFECTIVE LENGTH
72.938
OUTSIDE LENGTH
73.688
Let me break this down for you 10PK1851 does mean something. 10PK means 10ribs 1851 is lenth in MM which is 72.9" Even if it is 1850 it is still only 1mm off so for all intensive purposes 72.9"
Edited 1 time(s). Last edited Wednesday, November 05, 2008 7:58 PM
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I finally found the gatorback 4100729 belt. I phoned like every part store in town. Price $31.10. Woo HOO and it's in stock.
Wade Jarvis wrote:From my searching the Goodyear Gatorback 4100729 is stock size and 72.9" is stock length which makes sense to me.
I am betting you actually have the Goodyear Gatorback 4100722 on your car with the 2.6. Can you please double check what belt is on your car.
Yeah my bad, mine's the 72.2" one.
2001 Olds Alero (LD9)
636 whp / 543 ft-lb
@turboalero
NeoJuice wrote:I finally found the gatorback 4100729 belt. I phoned like every part store in town. Price $31.10. Woo HOO and it's in stock.
And as a bonus, you actually get TWO belts for that price!
IIRC, when the kit originally came out it came with another brand belt, but people had issues with them. They then switched to using the Gatorbacks.
I got it
![](/global/images/emoticons/ab.gif)
ill get it put on this weekend after i split it in half.
I checked my car again tonight. The belt is a 10PK1851 belt (4100729) but the one I bought is 10PK1850 belt (4100729).
Here is a post with a picture of the OEM belt
http://www.j-body.org/forums/read.php?f=40&i=77221&t=77221
Goodyear doesnt even list the 10PK1851 on there site. Where the hell GM get it from? As Wade Jarvis said above what is 1mm difference.
My new belt doesnt even have the blue logo on it either
![](/global/images/emoticons/ac.gif)
just kidding.
Got the belt on this weekend. It was tight but as long as you get the tensioner pulled back far enough and you have a spare set of hands you should be able to get the belt on in 10-15 minutes including the removal of the old belt.
Just thought i would give a update to anyone that looks at this post like i did for information.
For Stock pulley you can also use the Gates K060733 - Fixs prefect no slip or anything.
Its a 6 Rib belt but you can cut one rib off easily to make it 5. Its also a belt that costs less its 19.99 and readily available at any autoparts store. I am using it as we speak.
I've used the STOCK s/c belt with 2.8-2.5" pulley and it never slipped or anything.
what size is the tentioner pully on the 2.4 is it a 3 or 3.5" cause you could switch the tensioner pully
stock SC pully and a smaller tentioner might work the same as a stock tentioner and 2.6 SC pully
i think 2.4s have a 3.5 and i know the 3800 has a 3 so before you cut that check to see if you can get a 5 rib in the 722 and switch out your tensioner pully.
BTW some 2.4s had plastic pullys 3800s they used steel on the acessory belt
JBO since July 30, 2001