Ball joints?

Axledragger wrote:
Would you have the part number for the larger size lower ball joint for my p 30 chassis? Please help I can not find an information on the web. I found the moog K6129T but it was the wrong size Roger

If you have disc brakes on the rear of your P-30 chassis the part number you need is Moog K6511 for the lowers and K6174 for the uppers.

Would you have the part number for the larger size lower ball joint for my p 30 chassis? Please help I can not find an information on the web. I found the moog K6129T but it was the wrong size Roger

Octaneforce wrote:
Correction. I just went out and looked. Mine is rear disc.

Then you need the larger ball joints. Be careful because the mistake that almost cost us our lives was the parts guy saw HD ball joints listed under the drum brakes thinking if they said HD they must be better, but the tapered shaft is slightly under sized.I don't want to write a novel here but if you want to see the details look in the archives 2 years ago under Gjac. I ended up using the MOOG ball joint purchased from Henderson.

BINGO ^

Than you should have the larger ball joints instead of the smaller ones that were probably installed by a mechanic who didn't do his homework. The smaller ones are easy to find but the larger ones take some effort to find. He took the easy way out and you get to suffer the consequences 18 months later.

But, a good question none the less:

Can the HD ball joints for the P chassis be substituted for the lighter duty ones?

Any modifications needed?

Correction. I just went out and looked. Mine is rear disc.

I agree that the ball joints are the symptom, not the cause. There has to be a cause somewhere that is causing the premature wear. 18 months with failed ball joints over just a few thousand miles tells me you need to look elsewhere for the cause. Possibly severe overloading? Or as mentioned, the wrong size joints from the get-go.

Gjac wrote:
Be very careful when replacing ball joints on a P-30 chassis. Some P-30 chassis have rear drum brakes and some have rear disc brakes. Drum brakes are on the smaller lighter P-30 chassis. I had two front end ball joint failures because a local shop installed the wrong ones twice. I have disc brakes and they installed the undersized ball joints for drum brakes. And yes they will only last a year or less if undersized ball joints are installed. If you hear a clunking sound the tapered section of the joint is probably working back and forth in the hole work hardening the shaft and elongating the hole until you are going around a corner at 60 mph and failure occurs.

I think mine has rear drums. The gwv is 14,600. Will the balljoints for the disc brake version fit a drum brake truck? Sounds like an easy upgrade.

Be very careful when replacing ball joints on a P-30 chassis. Some P-30 chassis have rear drum brakes and some have rear disc brakes. Drum brakes are on the smaller lighter P-30 chassis. I had two front end ball joint failures because a local shop installed the wrong ones twice. I have disc brakes and they installed the undersized ball joints for drum brakes. And yes they will only last a year or less if undersized ball joints are installed. If you hear a clunking sound the tapered section of the joint is probably working back and forth in the hole work hardening the shaft and elongating the hole until you are going around a corner at 60 mph and failure occurs.