Trouble finding clutch parts
 

Hey all, I have a ‘65 with the 305e in it. Truck is in great shape but the clutch is starting to slip. I have read through the forums and I know I need the 04-528 from rhinopac or AMS but I can’t find one anywhere. Does anybody know where there might be some of these available? The weather will be turning soon and I want to drive my truck all summer. I don’t really want to take it all apart and ship out the original to get rebuilt with my truck sitting the whole time I wait. Would love to get it here so I can do it all at once and be on the road again. Photo attached of my truck for your viewing pleasure. Thanks for any help!

Re: Trouble finding clutch parts
 

Try this one:
https://www.amazon.com/New-Generatio.../dp/B000CNNV6K

Re: Trouble finding clutch parts
 

James, that one is out of stock too. Wondering if they are not being made anymore. I ordered one from a site in Canada and they cancelled too saying they don’t have any.

Re: Trouble finding clutch parts
 

Here is a place that can rebuild clutches.

https://kyclutch.com/?utm_term=clutc...hoC4e8QAvD_BwE

Re: Trouble finding clutch parts
 

what I found is it's easy to get the clutch pressure plate. Any 12" pressure plate made for a SBC will work.
This is the kit I used for mine.
https://shop.advanceautoparts.com/p/...62-1/5332559-P

the hard part is getting the correct disc. all the SBCs and L6s spin the opposite direction of a V6 305, so you'll need to use a different disc. I just reused the 11" one I had and it's all working fine.

Re: Trouble finding clutch parts - update
 

An update. The place James recommended above in Kentucky had one in stock and it appears to be correct with the collar on the correct side. I don’t have it installed yet but it’s here and that feels like a small victory already.

I also bought seals from a gasket company out in Washington I saw mentioned in another thread. I plan to do the oil pan and rear main seal all at the same time while I have things taken apart. Hopefully this summer I will be driving without any slips and parking without any oil puddles.

Thanks for all the wisdom here in the forums and for the help. I will update when it’s all put together in a month or so when it gets warm enough to work on it.

Re: Trouble finding clutch parts
 

I’m in the process of rebuilding my 64 with a305e , it looks like I can’t use a 12” clutch,the bolt holes on the flywheel are around 12.25” apart, is this right? The disc I took out was a 10.5. Is there any known part number that will work with my trans. This is starting to get frustrating

Re: Trouble finding clutch parts
 

Tin man you should start your own thread since your search wasn't part of the original topic.

But here's a link to a bunch of clutch kits I found when I had to do the same thing
https://6066gmcclub.com/showthread.p...ght=clutch+kit

You can also have them rebuilt for about $60.00 and they're good as new. Just search for "clutch rebuilder" or "clutch shop" plus your town and you'll probably find a good ol boy that does this for a living.

Re: Trouble finding clutch parts
 

I just put a 12-in pressure plate and I'm reusing the 11-in disc on my truck with no issue.

Re: Trouble finding clutch parts
 

???? Please explain how the clutch disc for SBC's and L6's "spin" in the opposite direction when all automotive/industrial engines "spin" in a clockwise direction when viewed from the front of the engine. To say that the clutch discs for SBC and L6 engines "spin" opposite of the GMC V-6 suggests that those engines rotate in a counter clockwise direction. There is another reason why SBC and L6 clutch discs will not work with the GMC V-6.

Re: Trouble finding clutch parts
 

I miss spoke. It's not that they spin opposite directions, it's that the discs are reversed.

Both of these are facing the pressure plate.
what works.
https://6066gmcclub.com/attachment.p...1&d=1699905723


what doesn't work
https://6066gmcclub.com/attachment.p...1&d=1699905810

Throw-out bearing
 

Throw-out/release bearing updated numbers. The "known good parts" page needs updated, so here is some current info.

my throw out bearing died on me, so I had to search for a new one. There are two kinds: Long and Short

Short: #614018 This number is used by many manufactures like Delco and National. Prices range from $11 to $45 ($67 at NAPA) for the same part.

• Bore 1.3775"
  Face 2.76" this is the part that touches the fingers of the pressure plate
  Height 1.252"

Long #1625 or NATIONAL G1625C

• Bore 1.3775"
  Face 3.0625"
  Height 1.699"

Just measure the face of your old one to tell which one you need. Mine is the short one and seems to be the common one. I was able to find it in town at all the major parts stores and of course Rock Auto. Rock Auto has some of the long and short descriptions wrong, so just go by part number and the dimensions.
___

other clutch info
---
11"Disk: none of the numbers on the "known good parts" page work anymore.
Nobody has this. As of now the only options are to get yours rebuilt or have a new 12" disk modified (flip it around. see post above)

---
12" pressure plates are easy to find, but it seems like you need to get the whole kit for those and the disk will not work out of the box and will need to be modified. The good news is the kit I bought had the short clutch release bearing and the pilot bushing would fit as well. It seems all the kits come with the short throw-out and a disk that won't work.

Re: Trouble finding clutch parts
 

I was told the Rhino-Pac/Platinum 04-528 was the only clutch kit that would work right out of the box with no modifications. It's a 12 inch, and supposedly the disc hub is assembled the correct way for the flat V-6 flywheel. I personally never used one, I had my original clutch rebuilt years ago. The 04-528 has been on back order for several months.

Re: Trouble finding clutch parts
 

Rockauto once again has the Platinum Driveline 04-528 clutch kit in stock as of this week.

Re: Trouble finding clutch parts
 

must have just been one day. Looks out of stock.

this solution looks like it will work though. https://6066gmcclub.com/showthread.php?t=51743

kit https://www.rockauto.com/en/moreinfo...=1993&jsn=1326
disk https://www.rockauto.com/en/moreinfo...10605&jsn=1342

Re: Trouble finding clutch parts
 

Rockauto notified me the clutch kit was once again available, I ordered one, and today they notified me it was out of stock! Typical Rockauto B.S., sorry for any confusion.

Re: Trouble finding clutch parts
 

it's usually just a renewal notification. anyways, you can delete it. There is a new kit available.

Re: Trouble finding clutch parts
 

That's the funny thing, I was getting notifications to renew the backorder. Then last week I got a notification is was available to order, which I did. Then a day later they said it wasn't available and refunded the charge.

Re: Trouble finding clutch parts
 

I finally managed to get everything together for my 60 4 speed with the help of Capitol Clutch and Brake in Sacramento. They were super helpful with a really tough problem.

Re: Trouble finding clutch parts
 

So, I get a notification from Rockauto this morning telling me the M-Pact 04528 equivilent of the Platinum Driveline 04-528 is available to order. I went ahead and ordered one, we'll see what I get. If anything!

Re: Trouble finding clutch parts
 

I ordered the Perfection Driveline 04-528 directly from them, and they only had the one in stock. It is listed in their catalog as fitting the 305 and 351 six cylinder.

It looks a lot like the photo of the M-Pact 04528, but it looks like it will not work.

So am I correct that this will not fit?

Re: Trouble finding clutch parts
 

I don't think that disc will work. This is the same old problem, the hub protrudes out too far on the flywheel side and hits the pilot bearing.

Re: Trouble finding clutch parts
 

disk is backwards.

these are the new numbers that fit
kit https://www.rockauto.com/en/moreinfo...=1993&jsn=1326
disk https://www.rockauto.com/en/moreinfo...10605&jsn=1342

Re: Trouble finding clutch parts
 

I ordered an M-Pact 04528 from Rockauto, and it is the same as the Platinum Drivetrain 04-528 as you can see in the pictures. Member 63gmc4x4 has used the Power Torque (O'Reilly's) 70375-HD1 clutch. It has an 11" flat disc and a diaphragm spring pressure plate. The GMC V-6's all came with 3 lever Borg & Beck style pressure plates which have more clamping force than a diaphragm spring type. The 70375-HD1 is for mid-90's GM pickups. M-Pact sells an 11" 10 spline disc part #383348 that has a flat flywheel surface, I have heard that this disc works on a GMC V-6 and can be used with a 12" pressure plate, but I have not tried it myself. Note that most GMC V-6's came from the factory with 11" clutches but a 12" can be used. Next week I will call M-Pact and see what they have to say.

Re: Trouble finding clutch parts
 

Another view of the M-Pact 04528 disc

Re: Trouble finding clutch parts
 

Jerrspud added the link to 63gmc4X4’s thread of a clutch disc that would work. I sent my disc that did not fit back to Platinum Driveline and had them find me one from a 1996 Chevy truck 1500 with the 4.3 V6.

Here is that disc, #381066, which cross checked to 70375 and 04121.
I have it here compared to a NOS GMC 11” disc I bought awhile back.

The springs are more recessed in the newer disc and it sits flatter, but the cone is taller on the original by about 3/8”.

Re: Trouble finding clutch parts
 

A few more photos; New disc on left.

Thanks to Jerrspud for updating numbers on the throw out bearing and 63gmc4X4 for his efforts on digging further to find the disc.

Re: Trouble finding clutch parts
 

The cone on the transmission side shouldn't make any difference. The 381066 disc is 11", correct? I have not called M-Pact yet, I am thinking about trying an M-Pact 384195ST1, it's a 12" diameter 10 spline 1.125" disc for a 1993 Chevy/GMC 3500 that appears flat on the flywheel side. I want to see if it will work with the 3 lever 12" pressure plate that comes in the Platinum/M-Pact 04528.

https://www.rockauto.com/en/moreinfo...=10605&jsn=648

Re: Trouble finding clutch parts
 

Yes 11" on the disc. That link and pics on the site seem looks like it may work.