Working on my 64' F100... Flipped the rear axle with 15x8" reversed wheels out back. (2.75" backspacing) Still working on mounting the fuel tank under the bed, but I thought I'd better check fender clearance before I get out on the road. How much movement is there usually in the rear end side to side? I have about 1/2" between the tire and fender.(Maybe a little less) Thanks in advance!
Stand beside the truck, grab the top rail of the bed, push back and forth sideways hard, I bet you get more than an inch each way. Time for a Panhard bar! How is the clearance on the inside, looks like those rims have an awful lot of positive offset.
I have 1" clearance between the tire and fender well on my Deuce roadster and it doesn't rub. 1/2" sounds a little close.
That looks pretty tight. If you haven't already I would replace the bushings in the springs and on the shackle. Then roll the wheel lip under. If that still doesn't get it I would look at installing a panhard bar. Sent via Illinois Bell Telephone Company's Car Radiotelephone
If you have parallel leafs there should be little or no side movement. If there is you probably need to replace the bushings in the springs.
X2 On the "What" Lots of lateral movement from parallel leaf springs even with fresh bushings. Sent via Illinois Bell Telephone Company's Car Radiotelephone
A panhard bar where one isn't needed, and roll the fender lip? The problem is the wheels, get some different ones with the right offset and the problem is solved...JMO.
Not to start a shit storm here but how in the world can you have lateral, side to side, movement with a bunch of spring steel bolted together and bolted to the rear axel? The only movement I can see would be in the rubber bushings moving around the mounting bolt. My Fairlane, Falcon and 53 all have parallel leafs in the back. My Falcon has less than 1/2 inch between the tire and inner fender and never rubs. My Fairlane has a touch over 1/2 inch and never rubs. So why do you say they have lateral movement??
A leaf spring moves in more directions then just a vertical plane. They also twist in different directions. Think about how the suspension cycles, it moves in an arc twisting the springs. The lateral movement is even more pronounced with the narrower springs on older vehicles. Sent via Illinois Bell Telephone Company's Car Radiotelephone
It is "spring" steel, that is what it is meant to do! Plus give in the shackles and bushings will always give some movement
Here's a link from someone who explains it better. http://www.timskelton.com/lightning/race_prep/suspension/leafs.htm Sent via Illinois Bell Telephone Company's Car Radiotelephone
"It's not what you don't know that get you into trouble, It's the thinks you know for sure that just are not so."
Also, the more arch there is in the leafs, the more lateral movement there will be at the axle. Also, if the leaf springs are not parallel, with either the front or the rear spring mounting points closer together then the other two, there will be less lateral movement. Back in the day when tire sidewall clearance was an issue for me, I figured I needed 3/4" clearance between the widest point on the tire and the closest point on the body. I had to be able to slide my fingers between the two easily. That would have been with Mopar performance cars. The correct fix is to get the proper wheel offset. But years past I have been know to flatten the wheel well lip, stretch the body a bit, even opened up more then a pair of wheel well openings for clearance. As a last resort, (actually, maybe before opening the wheel well up) add a panhard bar (though the bar was seldom added, doesn't take much to gain 3/4" on a previously undisturbed wheel well.) Gene
It is mostly normal tire roll/sidewall flex that is going to get you. A panhard wont do squat for that.
I didn't think leaf springs flexed much to allow lateral movement until I hung my video camera on the frame and went for a drive! Boy did I get a lesson in how much they flex and twist while cornering! That big stack of springs is thick, but it's down to a single leaf towards the end, and my video showed that area where it's 1-2 leafs really flexes under body weight in the corners, even with new poly bushings!
I waa tought that you should have 3/4" min. for sidewall flex. There has only been one time this rule has failed me, and that was on an ot truck. I cut a new set of tires on first test ride.
I had less than 1/2 inch clearance on my old 50 delivery using 15X8.5" wheels and 285/70s. With a full tank of gas and luggage for 2 weeks the car wouldn't rub on the outer body with only about 1/4" gap. However, the inner would occasionally rub on a big dip in the road, going around a sharp corner. Had original rear springs with fresh bushings.
Ok. It passed the "push on it really hard from side to side" test. The tire flexed pretty hard at the bottom. I do still have the original Gennies. They are going to be painted with the truck. If all else fails I'll run the 15x7's in the rear with the originals up front. Looks like I have about an inch of clearance upon closer inspection.
Hope to get it buttoned up and maybe painted this weekend. I'll post up how the tires hold up. Thanks to all for sharing your thoughts and experience!
Yeah...A panhard bar would bind as it tries to go through its arc...putting lateral pressure on the leaf springs. I'd love to see a video of rear leafs with an undercarriage cam while a car is hitting some good lateral G's. ..I wouldn't think they would deflect very much? Maybe I'm wrong. Posted using the Full Custom H.A.M.B. App!
It took awhile, but I found a video for everyone. While the the vehicle used is ot it still shows the lateral defection well. Enjoy. https://www.youtube.com/watch?v=Lev7Ifrln_g&feature=youtube_gdata_player Sent via Illinois Bell Telephone Company's Car Radiotelephone
I ran a 69 Road Runner on a dirt track (would have been about 74, low miles car in decent shape), stock rear suspension except for racing shocks, 10" wheels, 2" backspacing, cut wheel openings, 11" wide, old, stiff, dirt track racing tires. We had 2" of sidewall clearance between the tire and the stock inner fender, sitting in a static position. Noticed no movement from the push sideways test. During the 1st race, we had noticeable tire smoke coming off the turns onto the straight from the right rear wheel well, with little noticeable car lean through the corners. After the race, we had tire rub marks (nice clean, shinny, bare steel where the tire cleaned everything up) on the entire inner wheel well. The rear axle was shifting sideways 2" under load. We had to add a panhard bar. A video would probably scare the heck out of a lot of people. You should see how much the front suspension pulls sideways under loads! Gene
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