Shackle lift questions

[upnsmoke]

I am swapping rear axles yet again soon and am considering trying out a set of Belltech 6400 shackles while I am at it. Before I go ahead with it though, I have a couple questions for those that have run extended shackles with stock or close to stock leaf springs. For one, has anyone gotten significantly more or less than 2" of lift from the Belltech or similar shackles?

Do the springs lose a lot of their stiffness? I am considering running Explorer leaf springs for a little more lift, but have heard they are a little stiff, and may base the decision to use them or not on how much the stiffness of the spring tends to change with longer shackles.

Also, has anyone gotten a good measurement of how much your pinion angle changed with the shackle swap? I calculate that it would change by about 5 degrees if the lift is indeed 2", but that sounds wrong to me. Whether or not my math is correct, if pinion angle tends to change by a common amount from one truck to another I can have shims ready to go before I get started. No big deal either way, just thinking I could save some time spent on trial and error.

This will be fairly temporary as I plan to go to Chevy springs and a flipped hanger/shackle as soon as I have the work space, however I still need to do it as my current setup is not acceptable. Sorry for the long post and thanks to anyone that reads it and can help me.

 

[Sunk]

If I recall, the Belltech are 3.5 longer than stock shackles so that gives you 1.75" of lift. I think the longer shackles create more leverage on the springs, but I'm not really sure to what effect.

 

[upnsmoke]

I snagged a pair of Explorer leafs for $28 today. I'm going to put them on as I got them. If I get at least 1" of lift from them I can drive the truck with no other changes, so I will see how much stiffer they are than my current Ranger leafs. The individual leafs are significantly thicker on the Expo than those on the Ranger, so I am expecting a stiffer ride, though that is not what I am seeking. I will likely end up creating a combination Ranger/Expo leaf pack and using Belltech shackles. I'll just have to figure out the pinion angle when the time comes, no big deal. I should have the springs in this weekend some time. I'll get back with results.

 

[upnsmoke]

I should have the springs in this weekend some time.

^This weekend I said. That's about like me. Half a year later... I finally got Explorer leaf springs in my truck today. I also installed Autozone's equivalent of the Belltech 6400 shackle at the same time. I am currently using the next to last hole on the shackle, which makes it 6" between pivots and 2" longer than the stock shackle. I got about 2.5 inches of lift over stock, and since less than 1" of that should have come from the shackle, I would say that the Explorer springs gave me over 1.5" of lift. I was surprised by that, as the free arch of the Explorer springs seemed similar to my current Ranger springs. The Explorer springs I got could be clapped out. I thought they would have more arch than the Ranger springs.

I haven't driven the truck or taken any measurements yet. I am going to disassemble my Ranger leafs, reinstall only their main leaf tomorrow, and cycle them through their entire range of travel with the extended shackle. Based on what I see, I may decide to move my rear hanger forward one inch and/ or use the seven inch hole on the shackle (the last one). I have a feeling the shock will be the limiting factor on the travel for now anyway. I will also check the pinion angle once I get everything the way I want it. It appears to have changed significantly, but right now I'm just eyeballing it. I'm happy I finally got this done and can't wait to see how it drives.

Does anyone know off the top of their head if I could have any issues with driveshaft length if I move the rear axle forward a half inch by moving the rear hanger forward? If not I guess I will find out tomorrow, and I actually mean tomorrow this time, not another six months from now. No guarantees though.

 

[upnsmoke]

Well, I wasted most of the day today. I tried to beat one of the bolts out of the steel bushing inners of one of the Ranger springs, and managed to shatter a screw driver with a 2 pound hammer, sending a small piece of shrapnel into my wrist. I spent the next half hour cleaning up blood and wondering if something was still inside the cut. I wonder about myself sometimes. I did some research on shackle angle today, and figure I can move my shackle hanger forward at least an inch with my current shackle and spring combo. I have also verified that driveshaft length will not be a problem. I still need to check pinion angle.

 

[upnsmoke]

I finally got the truck back on its own wheels today. I ended up moving the shackle hangers forward two inches. I put a piece of 1/8" steel plate on the inside of the frame by the hangers to give some strength back to the frame where I drilled holes in it. I definitely lost some ride height from the blocks, but overall I am happy with what I ended up with. I have not driven the truck yet, but it doesn't feel a lot different just jumping up and down on the back with the shocks unhooked. I tried to get a picture of the shackle angle at ride height, but it was too dark under the truck.

With ranger leafs and 3" blocks:

With expo springs, extended shackles on the next to last hole, and no blocks:

It looks a little loaded down in the back, but it's not too bad I think. The front end is still a little high in the picture from being jacked up. The truck should be a little closer to level once it settles out. I may have to aim the headlights down a little so they don't shine in people's eyes. I haven't checked the pinion angle yet, but I it appears off a little at a glance. I have bump stops, spring perches, and U joints on the way. Once I get those done and get some different rear shocks I will take the truck for a drive and find somewhere to bounce it around off road a little. I am looking forward to driving it again. Hopefully it will not be too stiff.

 

[upnsmoke]

This picture shows the stance a little better:

I would rather have more ride height in the back, but this is temporary anyway. I can live with it for now. I forgot to mention I need to pull the bedsides out as well. They will interfere with the tires significantly if I do not cut or pull them. I may tackle that tomorrow.

 

[jmcleek]

This picture shows the stance a little better:

I would rather have more ride height in the back, but this is temporary anyway. I can live with it for now. I forgot to mention I need to pull the bedsides out as well. They will interfere with the tires significantly if I do not cut or pull them. I may tackle that tomorrow.

Knot the best pic in the world http://carphotos.cardomain.com/ride_images/1/3143/2249/7856124014_large.jpg http://carphotos3.cardomain.com/images/0016/79/04/16039740_large.jpg?v=1
Both trucks have Eplorer 8.8 and spring no blocks. 235x75r15s stock shocks stock shackles.

 

[upnsmoke]

I finally got around to measuring my pinion angle the other day, and found it to be two degrees from zero the wrong way. I am shooting for around two degrees from zero, but in the opposite direction from the the way that the axle tends to twist under acceleration. I'm sorry I am not able to explain that more clearly, but regardless, the most important thing is the amount of change in pinion angle that i saw. I will have to change it by four degrees to get it where I want it. I imagine that the pinion angle was not far off from the factory, and certainly not in the wrong direction, although I unfortunately neglected to measure it before I modified the suspension. I suspect that I got more than a two degree change out of less than a one inch shackle lift, which seems like a lot, but does confirm my original calculations.

All that said, I strongly recommend checking and, if necessary, correcting pinion angle after a shackle lift, because although my truck would have been drivable with the pinion angle as it was, it likely would have gotten out of the acceptable angle range under max acceleration. It may or may not have been a problem with my little 2.0, but I can imagine something with more grunt eventually having problems with a pinion angle as far off as mine is. I cut the perches off my 8.8 and will be welding on a new set at the desired angle. Also, for anyone interested, my 8.8 came out of a 91 Ranger with a V6, and has an 81 degree difference in angle between the pinion flange and spring perches, which is the same as that of the 7.5 that was in my 88 2.0. As a result, it would yield the same pinion angle in a direct swap.

Well, this about concludes my work on the rear suspension for now. I am planning to use urethane bump stops in the stock location because they are cheap. I am happy with the ride height for now. It actually gained a little when I tightened everything up. It turns out my rear shocks, Ranchos made for a 3" lift, are way too long compressed to use my available up travel, a result of poor planning on my part. I will upload a clear picture of the final ride height eventually. At this point I suppose I have done enough to the truck, or at least have enough planned for it, to warrant making a build thread. I'll drive it soon and give an update on the ride quality when I do. It seems similar to stock jumping up and down on the bumper with the shocks unbolted, so I'm expecting it to drive fine.