Rear Spring Flex (or lack thereof) with SUA - pics

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msahr

msahr

Joined
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I installed a MAF 4" lift, front flexes pretty good (stuff all the way into the fender, can't ask for better than that) but the rear absolutely sucks... see the pics.

My rear shackle is almost vertical. I looked at the way it moves when the suspension cycles and the shackle does move as it should, but I get a VERY harsh ride in the rear and the droop is practically nonexistent. Plus the rear axle looks to be too far forward in the wheelwell.

I thought about moving the rear shackle hangers back, getting longer springs (FJ45? Alcan custom? Something else?), longer shackles, possibly longer shocks, and I'm OK with it if I have to make driveshaft mods (I plan on a Marlin dual-transfer-case setup).

What am I missing here?

Rear flex:

DSC00666.jpg


Front flex:

DSC00669.jpg
 
Unfortunately that doesn't look particularly unusual for an SUA 4 inch lift springs setup.

From what little I can see in the picture, it looks like a longer shackle wil help your droop a bit. So will opening up the clamps on the springs.



Mark...
 
Thanks... I've seen pics but searched and can't find info on moving the sackle hangers back, and using a longer spring. Any thoughts on doing this (yes it will still be SUA)?
 
i think marks talking about bending those clamps up and open that keep your leaf springs in line with eachother, you'll get better flex that way

were you expected 4" lifted springs not to be stiff? lol
 
maybe loosen the spring bolts some so that the shackles move more freely? this has helped Ed (Degnol) with softening the ride ;)
 
I agree with all of the above. Drive it to get them broken in. Loosen those shackle bolts up a bit and open the clamps around the springs. That will give you a less stiff ride and let the springs move around more. Longer shackles will help the down travel too, but increase your lift (which you may not want?). You might not gain any more uptravel from longer shackles.

I think uptravel is overrated :D Its all about keeping the tires on the ground.

good luck-
Dustin
 
bandy rooster said:
wouldn't loosen the shackle bolts up lead to premature bushing failure...
Click to expand...

I dont think so. I am not saying loosen them up until you can wiggle the bolt. I mean loosen them up until you can spint the bolt with a wrench without too much effort. Too many people crank on these bolts like their rig will fall to pieces if they dont snug them down to 60 foot pounds. You want the spring to move in the shackle, not be binded to it.

-Dustin
 
I have the same lift on mine and it was stiff as hell for a long time. I wasnt able to wheel mine right away after I installed it but it was at least three or four trail rides before mine started to flex. I have a 1.5" shackle in the back. I also thought of moving the rear shackle mount because the angle wasnt very good. But now it is pitched back perfectly. I have heard of guys parking it all twisted up and switching sides the next day to help speed the process. I like mine now I can get the rear tires to rub now when they wouldn't for about 2 seasons, and no they have not settled either. Have patience. Good luck. Tom
 
My 4" lift was terribly stiff until I pulled the shortest leaf. Rides pretty well now for a cruiser and the price was right... 6 hrs of messing around with bunged threads. My recomendation, get new U bolts and cut the old ones off.

Additional information is the lift was on the truck when I bought it but I suspect it was an SOR package.
 
The springs achieve their lift with too few leaves per pack. Stiff ride city. Less leaves per pack keeps the price down. The engine weight helps the front springs flex despite their stiffness. I'm surprised the rear shackles are vertical unless they are longer than stock.
 
OK Wow lots of responses... Thanks

I've driven it a LOT since the springs were installed. Wheeled it 4-5 times, tried flexing it as much as possible.

The rear shackles are anti-inversion. The rods are threaded and only go in so far (they bottom out inside the shackle) I don't have them the nuts very tight, just snugged down.

I still would like to have the rear axle back some. The rear axle is definitely too far forward in the wheel well. I know it will move back under compression but not THAT much.

Going to loosen the clamps. They are most likely pretty tight, still just as the springs were shipped.

I like the idea of parking it flexed. Gee my neighbors already think I'm weird wait til they see this... :eek:
 
I think your thinking is a little counter-intuitive. I think that to accomplish what you say are your stated objectives are, you should try moving the rear shackle hangers slightly FORWARD.

1.Getting them away from the vertical will diminish the shock-impact value they currently have being diagonal to the frame.

2. Having the shackle kicked back in the static mode will give you a little more droop as well when you flex.

3. As you cant the shackle back, you will also lower the truck slightly, which will have the effect of moving the axle and the tire slightly further away from the leading edge of the wheelwell.

And, FWIW, IMO an OME-type anti-inversion shackle does not provide enough room for a 4" lift spring to move through it's full range of motion anyways.
 
get a set of 55 series springs, take the main spring and the military wrap spring, put the rest of the maf springs (minus the main and mil wrap leaf) with the 55 main and military wrap, bolt back on... move your shock mounts to suit, longer shackles, shocks, and longer brake line and driveshaft, and you should be away
 
So lots of people flip their springs when they are running SOA. Any one here have flipped springs on their SUA.? I can't think of any problems. You will gain 3.5" (back) Your wheel will now be centered in the fender, and your going to need all of that with a toy box IMO. I agree with Mark on moveing the shackle hanger forward. Then use a longer shackle.

aw
 
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