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Roll · 03-31-2013, 01:28 PM

A fellow member commented that my the rear lead springs looked flat after seeing a picture I had posted; I included it at the bottom of this post.

I see what the friendly gentlemen means and it caused me to crawl under and take a better look.

This is on a 2011 Ford chassis, 22,000 lb GVWR, 242 wheelbase.

Perhaps I am not recalling correctly but I though in the old days of rear leaf springs in cars, the long leaf connected to the frame via shackles and then the smaller leaves were stacked below the main leaf and the rear axel was attached at the bottom to the shortest leaf. (57 chevy that I snapped rear springs on when I dropped the clutch; typical teenager behavior). This made sense to me as more weight was transfered to the spring each progressive leaf would add to the stiffness of the set.

The ford is not the same configuration; the shorter leaves are stacked on top of the main leaf and the axle is attached to the bottom of the main leaf. Just the opposite of the old chevy; seems that the shorter leaves would add little or no support but it must make sense to a automotive engineer.

At any rate the point of the comment was that the spring looked flat, even bent up slightly at the axel with the full weight of the coach on it. Doesn't look healthy but of course may be exactly what Ford intended.

Do we have any rear suspension folks who know where a loaded spring on this chassis should sit? I am about 1100 lbs below my max capacity according to the scales. Note the rubber bumper is well off the axle indicating to me the coach is not riding low but again, would have to compare to a new chassis to compare.

Roll

grtharris · 03-31-2013, 03:25 PM

Short leafs go on the bottom, if they are on top the only leaf doing any support is the longest one connect to the shackle's.

garykk · 04-03-2013, 12:13 PM

I just looked at mine. I would guess the arch in the springs is about 1 1/2" or a little more from the centering pin to one of the shackles. But right now its sitting pretty empty with a full tank of fuel but no water, no clothes and groceries.

Murf2u · 04-05-2013, 06:00 AM

That looks about right to me. The 'new style' leaf springs Ford uses (even on my F350) are like that. If you look closely at the far end of the leaf in the picture you can see that all the leafs are joined at the end by a bracket and a very robust rivet down through them. In this way they work together as a single large leaf spring but with the ability to deliver a soft reaction to a little bump and a firm reaction to a big bump.

It works very well.

jamesrxx951 · 04-08-2013, 05:30 PM

i just looked at a 22000 lbs chassis today with a fleetwood body on it. The springs looked just like yours. The delivery weight was just over 18k LBS.

Dunner · 04-08-2013, 08:20 PM

I looked at pics of mine, but in all fairness, it was up on the jacks and doesn't look that much different. Me thinks you "friend" is trying to "act" like he knows what he is talking about. LOL. If the ride hight is the same on both sides, I wouldn't worry about it.