Coil Springs under 40s, again...

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

This is it

From the pics above of the ICON - and being someone who's collected the parts to 4-link the rear of my 40 "and" consistently being advised to cut off the rear frame so as to allow for good articulation and coilover placement (which I agree with) - I have to ask:

Looking at the ICON - the rear coilovers are located well inboard of the framerails, are short (guess you can do that being so far inboard) and overall seems designed as an all around vehicle, with only minimal advantages on the trail. Meaning - there are the obvious advantages to a linked system, the coilovers, bumps and swaybar are nice looking stuff, the D60 is nicer yet, but how much flex and what max size tire can that setup accomodate (knowing it's not meant to go big, but worth asking still)???

No doubt it's nice, but at the risk of blasphemy, is it any better than if someone modded an 80 or other newer LC setup with a 40 body on top (thinking of the FZJ45 by Gary that's frequently posted here)?

As to the front - I think this was kinda inferred by Kurt's comments about limitations of outboarding radius arms, but applying that thought to coilover placement - looking at the ICON front, and narrow axles - doesn't seem like you can have long travel coilovers and a stock 40 axle - without binding at some point and time (hence the shorter coilovers)?

While a nice setup - I don't see it going where I want to go.
 
Hey Ferg same reply as the WC thread...

got all the parts in late last month finally (steering etc). I have been cleaning up the shop to get the 55 outside temporarily to take this on with the mini truck. So I'm psyched, getting close to doing it, but no where yet. Thanks man and I'll definitely get ahold of you for some assistance. Cheers man, A
 
To the top for this old thread.. It only took me two years (really just last week) but here is the set up. Again this is on a '91 pickup I am super psyched with how it turned out. I wasn't able to get it as low as I thought I would be able to (as of right now). I can easily control height of the coils with the adjustable height buckets. I set it at approximate height of about 4" of lift and with my frame that does not have accommodations/design for a live axle, unlike a 40 or 60, I was able to max out at 5" of uptravel before metal/metal contact. I cannot say for sure but I anticipate about the same with a 40/60 that it will take some lift but not tons...

Specs:

GM 1 ton tie rod ends and linkage from 4x4Labs. Luke bent the arms in a spring under type method but because the TREs come in from the top (and are huge) they are still pretty tall.

I used all of the ballistic fab parts listed at the beginning of the thread. I intended to use .120 wall (1/8") DOM for the panhard and the drag link (because I didn't know how long I would need so I didn't get one of these from Luke) and bought GM TRE adapters from Ballistic and 3/4" heims with the matching rod ends for these as well. After I did this I found out 1/8th wall is too skimpy, it would work for the drag link but is probably too thin for the panhard even though I set it up so I would probably have no bending issues. Instead I went to Summit Machine in Utah (which is **awesome** and all sorts of neat stuff) and they sold me some 1/4" wall for about $11 a foot (I only needed 3'). I will use the .120 wall for the drag link now but have already ordered the right one that is about 1/4 wall from Luke though its also overkill and probably unneeded..

In all I'm pretty psyched with especially how it's turned out.. I have never had a 80 series and messed with its front axle, just wheeled with them and particularly in the rear was always impressed with the flex so I didn't realize how little they flex up front and why some folks have done 3 links & such... Because... They flex like s*** with the bushings and that is OK particularly with a locker. I think it will work really well for the intended use of the truck but it took so long to set it up even with the radius arms (way longer than I had anticipated getting all the angles right) that if I were to do it again I would just link it 3 or 4 link it and call it quits.. So in that regard Kurt and others were right The cost difference and honestly the time difference would be so minimal that 3 or 4 link would probably be superior.

This said it is still a nice, durable match to my Old Man Emu rear springs from Cruiser Outfitters and I still think it is a good front suspension and again will match the setup well. I like how durable it appears to be and how it will handle on the road just like a OEM 80 series... And with a locker it will wheel well. I am planning on using the original length shocks that comes with OME in the rear (8") and 10" shocks in the front because the mounts are outboarded from their location in the rear so it will need a little more travel. I will probably set it to 4 or 4.5 inches of uptravel (I'm not sure if this will be too much with the coils) and about 6" of droop or so... Which I know the radius arms will have trouble reaching I believe...

Placement of the panhard was the most difficult aspect of it all besides the time consuming aspects but this is also because I set all of this up from scratch. I think a "kit" would still do pretty well and relocating the axle is very easy -- basically as difficult as moving the upper links at the end of the radius arms. So that is nice...

Here are photos...
SM_113.webp
SM_153.webp
SM_168.webp
 
Hey there Mr. Steen.... Are you back or on your way back from Antarctica?

Here is the buildup...

More focus on engine specifics here

General Suspension and "Expedition" mods here
 
who did the arms?
 
4x4Labs with GM TREs. Also works of art.

Final product (finished last week). These pics are about 2" high in the front because there is no weight (no engine/trans/etc). The springs / suspension is very stiff currently.

attachment.php


attachment.php


I ended up having the bend the panhard to clear the diff because I mounted it too close. I think it turned out even better with the bend than if I left it straight. The 10" shocks really let if flex. I should have used 8" because I didn't think about less cycling because they are inboarded on the radius arm. So for 5" of travel they cycle about 3-4" which makes me think using the stiffer 255/70 valving of the Bilstien 5150 shocks was probably a good thing.

The suspension cycles and generally feels awesome. I am super excited and pleased with it so far (not having used it at all though).

I wish I had mounted the heim vertically though, but no big deal... This is only because this is the biggest limiting factor now with all of the suspension flex I will have up front. The radius arms and the heim will be the limitations...

attachment.php


attachment.php


attachment.php
 
I didn't cut and turn because I used a FJ62 axle that already has the cut and turn in it. With the radius arms the pinion angle reduces as it flexes (but the caster improves) so it is nice to have the pinion pointed upwards. Because I don't have the transmission in I basically played it safe and left it downwards.

I don't have plans to use limiting straps currently but I might at some point if they're needed... The suspension will get tested for this for sure...

Here is a pic with the suspension with tires now. With it set so there is 4-5" of uptravel (how I designed it) it matches the Old Man Emu literally perfectly... So in short it came out exactly how I wanted it to.. :)
SM_053.webp
SM_055.webp
SM_057.webp
 
Andre,
Just an opinion from already designing a panhard frame mount similar to what you have, I don't think you have enough weld surface on that mount. I would have keyed the plates around the frame, inside, underneath & outside. The panhard axle mount *should have the same relationship as the frame. It looks as though it's highly misaligned as is. You will need limiting straps, BTW. Depending on the rate of those coils (if they're really bouncy), you may want to think about a sway bar location.
One other thing to think about is brakeline routing. On my rigs, I run mine along the firewall & use a long braided line to tie at the top of the diff to a junction low on the firewall, just above the starter area. No hanging lines off the frame to get snagged. Hope this helps :D
 
The Ballistic Fab panhard I ordered was slightly more heavy duty. The weld is wide and long, 2" and on both sides, burned in really well and also into the inside and far plate. I do agree it should be beefy but I think it will be just fine.

I flexed the suspension heavily and the reason the panhard mount isn't parallel with the frame is it cycles perfectly with little flex in the suspension bushing. So I know I won't have any issues with that. If I had used the heim on the frame side I would have maybe taken that route...

Limiting straps are definitely a good idea. The photo with the heim closed to maxed out shows it at 10" of droop with no coil springs. They only extend about 3" with no weight. The heim could be damaged but the real question is if the radius arms will let it flex that much. When the driver's wheel is up the heim will have less extension on it. When the passenger wheel is up it will increase the heim angle so there may be no issues there as well.

So the point of all this is I'll test it before I run it. If it needs limiting straps it will get them...
 
Well I decided I was being subbord and will just buy some limiting straps... They are also reasonable enough at about $50 or less and will be easy to install. Better safe than sorry...
 
Andre,
Just an opinion from already designing a panhard frame mount similar to what you have, I don't think you have enough weld surface on that mount. I would have keyed the plates around the frame, inside, underneath & outside.


Arm chair opinion here, I concour on this point and would run at least one peice of plate up a few inches onto the frame. Even if it is a thinner material, it would drastically beef it up:cheers:

Rob
 
That is exactly what I decided to do.. The engine goes in very shortly. I'm going to scab plate it before the motor mounts are welded in (so I can weld the piss out of them as usual) and I'll extend it down to get some additions there... Good call guys. Limiting straps will also be here in a couple days. Came to about $40 at 4 Wheel Parts (local) but not in stock. $2 in sales tax but free shipping, totally worth it...
 
@ Dieselcruiserhead:WOW that looks realy cool.

@ all the others,this is even possible on the cheap for your 40's.I did mine with 61 axles with FF and OME lockers.I also bought an old 80 to part out and simply used all the arms and brackets off the 80 to weld on the 40 chassis and the 60 series axles.I am using this setup now for about 6 months for all the hardcore trails and events here in Panama but also drive it on the highway with great results.

This is something you can build for a few 100 bucks if you got some time(did it in one week:doh:)and you do not need to buy expensive equipment and order a months salary on little parts.In this country I am living now you can't even get the metal plates in the size you want:bang:,so it's all about recycling other stuff(witch I realy hate:mad:)
calovebora 023-800.webp
calovebora 042-800.webp
calovebora 067-800.webp
 
...@ all the others,this is even possible on the cheap for your 40's...

Nice :cool:

I'm by no means ruling it out and in fact all the recent talk of it as well as Andre's truck build have had me thinking again. I stand by my logic that it will take a person that has above average fab skills, time and access to the used parts to make it a clear winner versus that of say a traditional SOA or on the opposite side of the spectrum a true linked suspension with gobs of wheel travel.
 

Users who are viewing this thread

Back
Top Bottom