Loose Axle???

 

 

Surely this CAN'T be good...

 

 

 

I was out in my coach the other day, and while working under the engine cover, I glanced down at my various parts when I realized that something just didnt look right... Can you see it?

 

I know for a fact there SHOULD be 6 bolts in there holding that on...There are now 2, and they aren't exactly tight. I am sure glad I was not driving the GMC when the other 2 let go!

The strange part of the whole thing was I didnt hear any kind of odd noises at all. I guess the transmission was replaced like I was told. I was not sure if it was simply a simple thing like maybe someone forgot to put loctite on the bolts...Or just didnt tighten them all the way.

I immediately grabbed my phone and called Jim Bounds who told me not to move it, and to block it where she sat so it couldnt roll. He also told me that these bolts are "one use" because they stretch, and are worthless afterwards. He told me what kind to buy, and I have been searching for them here, with not much luck I will probably have him send me up 12, as I will not chance the other side either...

 

I did some additional reading and I found that several owners have used bolts and lockwashers supplied by a company called McMaster - Carr. They are very easy to shop online, just enter the part numbers, add to cart, pay, and they ship. That was easy...

These are the part numbers...

 

 

91271A644 This is the number for the bolt. The above cap screw is a good replacement for GM# 394777 which is still available from GM, at $8.02 per bolt. The fact that it is threaded full length is not an issue. The torque applied to them keeps the flanges tight together. You get a package of 25 which is more than plenty for both sides. These bolts exceed grade 8 standards, Rockwell hardness is C38-C42. Minimum tensile strength is 170,000 psi. I will trust these, as have other owners with no issues. I paid $9.02 for the pack of 25 on 3/6/08.

 

90073A231 High Collar Lock Washer... Although it is not in the our Z78 parts book this
washer is available from GM as #9439512. This washer from McMaster is a perfect replacement. You MUST use a lock washer on these bolts or they will do exactly the same thing again... By the way, the price on these are a mere $4.53 per pack, and you get 100 of them!

All told, I paid $13.74 for the needed parts, so I am satisfied. I will post more when I complete this job. The drivers side looks like it will be easy, but the pass side may not be so easy...

 

Today, March 23, 2003...Easter Sunday, to be exact...Not much else to do, so I figured I would drag myself out to the coach to finish these bolts. Actually, it was a lot less involved than I figured it would be. The bolts require the use of a 3/8 12 point socket or a wrench. It was recommended to me NOT to use loc-tite as it really isnt necessary as the lock washers are more than sufficient, and will be easier to remove in the future if need be, such as the installation of Jim K's final drive!

The end result is shown here...

All nice new shiny bolts and we are ready to roll!

Here is a photo of the old bolts...These 3 are the only ones that were left on the coaches drivers side, and as the photo shows, the threads were worn off...

 

I am very pleased that I had no other damage to contend with, but all the rest of the bolts have been replaced.

 

Another task completed!