Posted by Matt Wilson on Tuesday, January 27, 2004 at 4:00PM :
In Reply to: Interesting Spring Discovery posted by Marty on Monday, January 26, 2004 at 3:50PM :
Well, I got another possible answer from one of my engineering buddies at work. He said with grease between the leaves, there is a tendency for the leaves to deflect more than they should during braking. The axle normally wants to rotate forward when braking, causing the springs to "wrap up" a certain amount. But he says that with grease between the leaves, this spring wrap-up is excessive, and this causes extreme angles between the driveshaft and the rear axle pinion, causing u-joint problems and also causing excessive slip yoke motion. He had a GMC Yukon that was lifted a lot, and when he'd brake hard or take off hard from a stop, he says he could hear the rear u-joint popping, due to the excessive drive shaft angle that occurred for just a moment.
I'm not sure if this is really such a big deal as he says, but it's worth consideration. Considering how stiff the Power Wagon springs are, I doubt that it would ever be a problem.
Anyway, I saw your post below, with the answers the spring man gave you. Sounds like it's worth a try. After you do it, please let us know how it comes out, because I might want to try it too.
Matt