Well, I got some pics back yesterday so I thought its time to update you all on how my puller is cooming along. This update has to do with the rear suspension. The heavy 1-ton springs were cracked and rusted very bad off of the 76 so I decieded just to go and order new 56" springs from a local shop in town. The Springs consist of 12-7/16's leaves and arched to give me 2" of lift over stock height. The 2nd leaf under the top one is special in the way that it is "wrapped" meaning that on both ends in stead of ending just in front of the spring eye where the top leaf goes around like most other leaf springs, it wraps over the top leaf preventing flex and making the whole pack double the spring rate.
After getting the leaf springs and knowing I only had 2" of lift out of them I decieded to fabricate up new spring hangers to get more lift and also to beef it up a little because the stock hangers are great for stock but I was doubtfull how they would hold up dragging 45,000 pounds!!! So what I did was make the hanger out of 5/16" steel and made them so they gave me an extra 2" of lift at stock height over the factory hangers. Then what I did was make a back place out of 3/8" steel that bolts to the frame and is 14"x11". I then made the hangers adjustable on this back plate. So in the end when they were finished I had 6" of adjustment out of the hangers them selves, then 2" of lift out of the hangers because they are 2" lower than the stock ones and then there is also 2" of lift out of the new springs so thats a grand total of 10" of lift in the rear suspension. Now what I am going to do is where the back plate mounts to the frame there is about 7" that stick down below the frame so I am going to atatch a cross member from one side of the frame to the other and am going use that for the front part of my hitch that has to be a 1/3rd the length of the wheel base of the truck and has to be from the centre of the rear axle back. It is also going to be adjustable so I can tune it into the sled and there for get the best angle for pulling.
Anyway, here are some of the pics and I will explain which each one is.
Ok, this is the front hanger and has ALOT more beef to it than the stock hanger and is made of 5/16" steel and is super stong and it alone gives me 2" of lift.
This is the rear hanger and it looks different than the stock hanger in the way that there is actually a CUP sort to speak, that the rear shackle sits in and through out full susp travel the shackle doesn't make contact with the CUP so it adds more strength to the hanger as well as it also gives me 2" of lift.
This picture is the hanger atatched to the back plate which is bolted to the frame. At the height this pic is taken its at the 1" lift height which is aprox 5" of total lift counting the 2" I get from the hangers them selves and the 2" from the springs. You can also see all the holes below the bolts in the hanger and the back plate. All the hardware is grade8 bolts and using dimpled lock nuts and once I get the suspension "tuned" I will use the special lock washers I have that take 2 times the force to loosen as it did to tighted them.
This picture is the same hanger only at full drop which is giving me a total of 10" of lift out of the whole suspension. I doubt that I am ever going to need 10" but I decieded to put it there just for saftey sake[img]/wwwthreads_images/icons/wink.gif[/img]
This next picture is of the leaf spring atatched to the hangers and everything setup and is ready to bolt on the 14bolt FF.
This picture is of the spring and you can see how thick the pack is. Its is just over 5" thick and should give me as close to No-Flex as it can.
This last picture is a little blury(actually they all were!!!) but anyway, it is of the spring end and you can clearly see how the 2nd leaf is wrapped up around the top leaf. What this does is restrict the movement of the whole leaf pack and more than doubles the spring rate for the whole pack.
I got a great deal on those leaf springs for them being custom made. I paid $500CDN or about $350US and they are 56" springs and the guy at the shop were I got them from said that without the 2nd leaf wrap on them they would be rated at about 1.5tons+ and because of the wrap on the 2nd leaf that pretty well doubles the spring rate making it about 3tons give or take abit. I unfortunalty have the pic's of the axle atatched to the suspension still in the camera and will post them as soon as I can. But when I stand up on the frame I can jump up and down (I weight 225Lbs) and the suspension only moves aprox 1/4" and thats just the movment that it takes for the wrap on the 2nd leaf to touch the top leaf.
Well, thats pretty well it for this part of my up-date. I do have some pics of the 14bolt rear when I was rebuilding it and swaping the 4:56 gears for the 4:10's and also what it looks like now with out the heavy brake drums on it. I will try to scan them tonight and post them on here.
Oh yeah, if anyone wants dimensions of the hangers or anything feel free to ask me. It cost me $80CDN in steel to make them and paid my buddy $50 to weld them all up for me and do the machining.
Ryan
93 GMC Yukon
Chevy SuperStock 4x4 Truck Puller
Great Lakes Truck & Tractor Pulling Association
http://www.greatlakespull.com