blocks and leaves out back...shocks don't fit

[greasemonkey]

so, while I was swapping my rear axle to a 2nd gen D70 this weekend, I discovered that the shocks installed were at length or just overextended with the truck sitting at ride height...so the axle/suspension could only compress and could not extend past ride height, which explains the extremely rough ride when unloaded.

assuming the previous owner installed the wrong shocks and having them off, knowing they're shot, I ran to napa to get two new ones. well, these shocks actually have resistance/pressure on them but...they're the same fit, just long enough fully extended to install at the truck's ride height.

now I'm unsure of whether or not I have the correct amount of springs or the right blocks, here's what I have:

blocks: 6"
leaves: 7 leaves 2.75" thick overall, plus the overload spring above the main pack.
shock mount length @ ride height: 24.5"

is my suspension not stock or did napa get me the wrong shocks?!?

[GO OVRIT]

Factory is 6" blocks and 2.75" worth of springs.

[greasemonkey]

in light of that, I'm at a loss as to why these shocks aren't long enough. when I was at napa, the guy said there was no designation of 4x4 or 2wd necessary, only option on the 250 was the axle weight rating, which is the heavier one since it's a diesel.

anyone willing to climb under their truck and measure the distance for the shock mounts at ride height?!

[PToombs]

At SOP when we swapped beds on DPucketts truck, he had 2 sets of shock mounts. He had swapped the axle. 1 set mounts to the cross member, the other set mounts to the frame with a different bracket, it sticks up above the frame. IIRC, the C & C mount sticks up, the pickup is on the cross member. The difference in length is alot.

Ahh, after reading that, I know it's not quite right on the mounts. Maybe he will chime in and correct this.

[GLHS]

My shocks measure 25.5" long fully extended. at rest it sits at 24.5". I have the same 6" block and 7 leaf pack with one over load. Looks like you have the right shocks. The ones you bought are gas charged. That's good.
I can't tell in the picture but your bottom mount looks goofy to me.

Just thought of something; If the 2nd gen axle has more pinion angle than stock, the spring perches might twist the rear of axle down which would extend the shock.

[greasemonkey]

are you saying there are two different 1st gen mounts? I know the 2nd gen has shock mounts welded to the axle bottom, completely separate from the u-bolt pads; and they go up to the frame, fore and aft.

I'm going to go back to napa tomorrow and see if they can look the shocks up by size and just get some longer shocks, hopefully that works. the truck rides surprisingly well without shocks on it, especially since the installed were acting as limiting straps!

[Ace]

I think when you start mixing and matching springs, blocks, housings, etc. it's best to just measure and get the shocks you need based on whatever length is called for depending what your combo ends up looking like.

[greasemonkey]

only other thing I thought of was that the axle tubes/mounting pads could be different but they're not; both measure just over 4" from the top of the mount pad to the bottomw of the axle tube.

as far as 'mixing and matching' everything...I didn't touch the springs or blocks and the axle tube and mount pads are the same dimension; I'd have the same problem whether I swapped to the 2nd gen axle or not.

here's a pic of the u-bolt pad/shock mount, is this what it's supposed to look like or is it possible I have the wrong pads?

[Ace]

Sounds like it had the wrong shocks on it to start with, then.

[greasemonkey]

Sounds like it had the wrong shocks on it to start with, then.

whether it had the wrong shocks to start with or not, the new shocks from napa that are listed for my truck don't fit...which seems to indicate there's something not right other than shocks.

the upper shock mount/crossmember bar doesn't appear to have been relocated, if all the other dimensions are the same, only thing I can see is if the u-bolt plates are wrong...but that takes me back to getting longer shocks instead of trying to hunt down the right plates.

should I jack the frame up until the axle hangs and use that for the extended shock length? as far as I know, I'll need to know extended length, ride height and give an educated guess as to what the compressed length is...

[Ace]

I'd go for extended length as measured +1, for fudge. It's probably pretty hard on the shock bangin' out to the stop all the time. Then I'd measure it fully compressed, and call the techs that work in the co. that make the models I'm interested in, to make sure I choose the right one that travels the distance between those two numbers.

[greasemonkey]

awesome...went back into napa to return the shocks and have them look it up again. well, I told him to make sure it's a 5.9L diesel and not the 5.9L 360, that's where it got interesting. their system doesn't show a diesel for the 91-93 trucks for shocks. called the dodge dealership, not available from them.
so out came the paper book, found the 4x4 diesel 250, finally. said the extended length was 28.5". now at a ride height of 24.5", I'm thinking it's not very realistic for me to ever extend past the axle hanging on the springs. just in case, though, he's going to check tomorrow morning to see if I can get some 30" extended length shocks...if not, I guess the 28.5" will have to do. It's not like I'm going to be desert racing this thing or even going on fireroads a whole lot (not with 2 open diffs anyway...).

[Philip]

The NAPA gas magnium shocks are number 34771. These are for my W350. I do not have overlaods on the truck. But that shouldn't change anything. The overloads do not increase the ride height empty.