atom631

my 85 p/u is running allpro 4" front springs and the shackle angle is basically vertical. even after about 10-20 trail rides it hasnt relaxed. i am assuming this is limiting my down travel as the shackles are already swung all the way down. so i want to correct the issue and im not sure what the best approach is.

the way i figure it, i have it narrowed down to 5 choices.

1.) move the spring hanger back (would be a bitch). would also shorten my wheelbase, which im not really wanting to do

2.) use another off-the-shelf spring. i looked around and whether allpro, marlin, davez, trail-gear...they all seem to make the same length front spring (which makes me wonder how my shackle angle is so steep b/c its in the exact spot it should be)

3.) Go to RUF setup. I know this is probably the best choice. What Im worried about is 2 things. What leaves should I take off my allpro 4" kit to get it back to the same ride height? and do i need to run a different shackle becaus of the added length and hitting the body mount? If so, what shackle length or boomerang?

4.) Pull a leave or 2 out of the pack now. Im thinking this will relax it a bit, but not much. also will probably make it extra soft and either go negative or bottom out the shock/hit the bumpstop alot. If i am wrong, and this is a good choice, what leaf to pull?

5.) f#ck leaves and go 3 link!!! except $$$$

below are some pictures to get a better idea of what im talking about:

atom631

oh and here is a link on youtube to my truck doing some work... it does work well...but i want it to work better!!

http://www.youtube.com/watch?v=d86h2...w&feature=plcp

skunkwhat

Where is the front hanger in relation to the frame? can we get a picture?

atom631

that middle pic is the best i have right now. i will see if i have anything online. otherwise i will snap a pic when i get off work.

atom631

i think this is the best i got for now.

4Crawler

iTrader: (3)

What is the arc and chord lengths of the front springs you have on there now? (arc length is measured along the arc of the spring, chord length is eye to eye distance).

atom631

Springs are stamped "Front33", which should be the 4" kit from All Pro. To double check I emailed them awhile ago and confirmed I have the correct springs, which they said they are...and these are specs they provided me:


Over alllength 46 ¼
Pin to front21 5/8
Pin to rear24 5/8

4Crawler

iTrader: (3)

Well, that is close to what the stock rear springs measure:
- http://4x4spot.com/misc__spring_information.htm

Maybe put in the stock man and mil-wrap leaf from a stock rear pack and then the rest of the AP leaves and see how it looks. The ~1" longer main leaf should push the shackle back a bit:
- http://www.4crawler.com/4x4/CheapTri...l#Applications

atom631

thanks for the feedback...but i am a little confused by what you said

from that chart you linked (awesome chart btw, thx) - stock rears are 48", making them 1.75" longer than what I have now. It also looks like it will move my axle forward another 1" or so, which might not be a bad thing..but now I might have issues with my steering. A stock pack from a 80-83 looks like it might keep the axle in almost the same spot and just add 1.75" back.

here is a pick of my setup now so you can see where my tie-rod and draglink are:

4Crawler

iTrader: (3)

I think that table is a bit "generous" in the lengths, I think ~47" arc length is what I measured, like 20.5" and 26.5" f/r splits.

Or for removing a leaf, try pulling the 2nd one from the bottom and see how it works and/or swap in a stock rear leaf of similar length to one of the AP leaves to soften a bit. Or run a shorter spring shackle, shorter shackle = more angle for a given setup.

atom631

didnt think about using a shorter shackle. i am assuming a shorter shackle would provide less down travel then a properly setup spring and the current shackle i am using?

4Crawler

iTrader: (3)

Shorter shackle will move a bigger angle than a longer one. That will give more change in vertical distance from frame. Maximum extent of droop will be less, but you may see more up-down travel distance, since with a longer shackle all you see is how much the spring flexes. When you get the shackle moving back and forth, you see some contribution from the shackle moving plus the spring flexing.

Might sped some time measuring things on the truck to see what is limiting down travel. Might be the shocks, or the bushings binding up or something else. Also, the springs have only so much free arch and that is as far as they will droop on their own. That is one reason I went with the '83 instead of '85 rear leaves as the '83s had 3" more free arch than the '85s, meaning they have 3" more droop.

atom631

great info. thank you!! So I guess I should be on the hunt for a 80-83 rear pack. I could also possibly do that with a shorter shackle if it still isnt relaxed enough.

as for measuring.. what would i actually measure to determine if my downtravel is limited? this is my first yota, so i dont have another truck to compare to. im not even sure it actually is being limited...i just know its not right being at almost 90 degrees.

4Crawler

iTrader: (3)

Measure everything you can think of an try to get your head around how it all works. Basically what I did below::
- http://www.4crawler.com/4x4/4R_suspension.shtml#PhaseII

Let the axle hang straight down to measure the free arch, then twist it up to see if you are getting the same arch. Measure shock up/down travel, etc.

atom631

Excellent thanks. Ive got a lot to go on now. Thanks for the help.

atom631

4Crawler: I pm'd you an off-topic question. I appreciate the input.

I did some quick measurements this morning before work.... My shack is 5" e2e and from e2e on the spring I am showing 45", measuring straight across... I'm not sure what that means exactly since that measurement is under weight. I would imagine it would be even shorter without the leaves flattened out from the weight of the truck. Maybe these aren't the correct springs after all?

Here are a few more pics of my truck




And here is one as she sits with street pressure but loaded and ready to wheel.

atom631

ok..so after taking 4crawlers tips, doing a lot of reading and searching for new springs... i scored a set of brand new (how, i dont know.) set of rear 83 leafs. The guy I bought them from removed the overload leaf and added in 2 leafs from a YJ pack. I also picked up a set of stock 86 rear leafs in case I needed to make 2 sets.

I measured all the corners using a forklift. Like an idiot I left the sheet at the shop to give you the exact before/after measurements...so I am remembering most off the top of my head.

Here is a pic difference of the AllPro 4" leaves vs. The 83/Yj rears


Here is my shackle angle before


Here is my shackle angle after


Once I had the new springs, I check for ride height and determined they were perfect as is! My original frame height was 24" and it then went to 23". After I did some work to the rear (moved shackle angles in, went with creeper joint shackle hangers, removed bottom 2 leafs from rear pack) my final ride height was about 22.5"

Ride height before


Ride height after


Rear shackle angle before


Rear shackle angle after


Now for the flex test...again, I don't remember the exact numbers, each corner was slightly different... but I was averaging about 27"-28" from lowest lug to the ground when I lifted the rear wheels (testing front suspension). After the new springs I went to about 33-34".

Before:


After:


When I lifted the front, I went from around 25" to about 28.5". I also noticed, I had a broken 3rd leaf on the passenger front!! My Allpro leafs were going negative much more than 83s too. I am now bottoming on the shock and bump stop simultaneously..so I will have to put a slightly longer bumpstop on. I feel like I can tweak my rear leafs a little more to get better flex out of them, I think that they are a little stiff for a bobbed pickup. Im thinking If I remove one of the longer leafs and add back in a shorter leaf it will maintain same ride height but be a little softer.

Before:


After:


One issued I had with both Allpro and the 83 leafs was my pitman arm is forcing my TRE to contact the springs. I went from a stock arm to trail gear arm and that helped a little, but not enough. The 83 leafs made it even better..but still not enough. So my next step is going to a full flat, but I really dont want to have to notch the frame. Does anyone know if someone makes an arm that is 1/2 way between flat and the trail-gear drop arm? That would be perfect as I only need about 1" to be totally safe (notice how much shock is left).

Pitman arm/TRE issue:


Here are some pics of the rear before the creeper joints and leafs gone


And after


more testing of the rear springs, before:


after


The WB is now about 107". I forgot to measure the before, DOH! I also need to lengthen my brakelines and I trimmed 1" off my rear bumps.

Overall Im really happy with the results. A little lower, a little longer and a little more flexy. Should be awesome on the trial.

4Crawler

iTrader: (3)

Dropping for the front spring hanger is one option to get more drag link/pitman arm clearance:
- http://www.4crawler.com/4x4/CheapTri...ringHangerDrop

atom631

that would raise my front end back up again though, right? id like to avoid that. trying to keep this truck as low as possible.

what pitman arm is that you are running in those pics? that might be perfect for me.

4Crawler

iTrader: (3)

You would see about 1/2" of lift for every inch you drop the front hanger below where it is now.

That is the older AllPro heim joint pitman arm. You would need a drag link threaded for the 3/4" heim joint end to work with that type of arm.