We have a 1977 F-250 that we use in local truck pulls. We have added about 5 of the next to longest leaf springs on each side in the rear to keep the Dana 70 from piviting and breaking u-joints. Upon doing this, we realized that the old shocks wouldn't work. For a couple of pulls we went w/o rear shocks. Problem being that the truck bounced VERY badly without the rebound control that shocks provide. One of the other pullers recommended Rancho 9000s. I need to know if the 9000 would be a good shock for me? Are there any better ones for my application? I was told to stay away from coil over as they would likely not help with the hopping. I need a rear shock that will eliminate the hopping in the rearend.
The 9000 shock is a reasonable choice as it provides you with some adjustability. If track conditions change and you end up with more bite, you can dial up the shack to increase traction. Might be a good way to go.
You do not want to go with a coilover since you have leaf springs already. Using a coil spring and a leaf spring together on the same axle is not a good way to go. Spring rates are very different, and they react differently under equal load conditions. You have a damper problem, so controling the axle is a must. Any shock will be better than no shock, but the 9000 will be adjustable.
While I am not a big fan of traction bars, I believe that they would be a decent option here to control the axle. If you are pulling, you may not need the extra payload capacity of the additional springs, and are trying to use springs to do the majority of the axle control. If you take notice of the main band of the spring, you will see that only one leaf is actually responsible for locating the axle. This can and will break. Without this, the axle will no longer be able to stay under the truck. Big time carnage. If this is primarilly a pulling truck, you may walk around the pits to see some of the other combos that others are having success with.
Thanks for the wisdom . We used ladder bars all last year with great success. However, rule changes in our area put us in the open classes even with just bolt in ladder bars. The open classes are welded suspension, headers through the hood and 1100+ HP trucks. We run about 1/2 of that and would like to maintain the "streetability" of the truck. So this year we removed the ladder bars to get into classes we can compete in. We then added the leaf springs to compensate for the loss of the ladder bars. This has seemingly solved our busting u-joints, but increased the hopping due to the deleted shocks. Are the Rancho 9000s my best bet?
That is a pretty hard question to answer, as there is always some type of variable that may not make it the "perfect" shock, but the 900 does offer plenty of advantages that would make it a pretty good choice.
I see where the removal of the shocks would have made a difference on axle control after the remova; of the traction control devices. Here is something to consider as you are building your springs, or if you decide to modify them. Use a military wrap style spring. These can be made from an old front spring, and will be quite a bit more secure if and when the main spring decides to fail. If a small nylon bushing is placed between the main band and the second miltary wrap leaf, you can pre-load the susprnsion a bit, and will do a very good job of pinion angle control. Many oppinions are that the spring has to be very stiff in order to control axle wrap, and I have found that this is just not so. I have been fooling around with different springs in the back of my junk, and I am having very good luck with a very flat spring that is only 2.5 inches wide. No traction devices and a very stock valved shock. I did re-locate the mounts for the shocks, and tuned the spacers between the leafs, I have also used an offset in my leafs. Meaning that not all of the leafs have the alignment hole directly in the center. This helps control axle wrap without the compromise of adding weight or limiting flex, and ride comfort.
I run 39.5 inch tires and can spin em up on asphault without rear wheel hop. Works very well in the sand and mud. Sand used to be tricky to drop the hammer in, because the front and rear used to hop pretty hard, but that has been eliminated now, and I can get deep into the nitrous in sand.
I think you would be doing an alright thing by using the 9000 shocks. Maybe consider the 9000XL's, as these are a little larger for heavyier trucks.
Good luck.
Join Our Site - Its free, quick and easy!
. We used ladder bars all last year with great success. However, rule changes in our area put us in the open classes even with just bolt in ladder bars. The open classes are welded suspension, headers through the hood and 1100+ HP trucks. We run about 1/2 of that and would like to maintain the "streetability" of the truck. So this year we removed the ladder bars to get into classes we can compete in. We then added the leaf springs to compensate for the loss of the ladder bars. This has seemingly solved our busting u-joints, but increased the hopping due to the deleted shocks. Are the Rancho 9000s my best bet?
