Lou Bell
Mudrunner
Reged: 04/27/02
Posts: 394
Loc: central CA
|
|
Having had Gabriel air shocks ("highjackers") on my last truck and currently using them on my firewood hauling trailer I would like to make some comments about your application of them.
The first is that when you cross link them, the vehicle behaves more "top heavy". This is a much bigger concern on-road as it can lead to excessive body roll. Off-road, the only problem I see is in off camber situations. The downhill shock will compress, pushing the air into the up-hill shock. Not what you want when on a side hill. You are right in saying you will need a sway bar. This will definately help. I have the shocks on my wood trailer on seperate air circuts now to help negate unwanted roll and side to side pitch on-road. Maybe you could install a cab mounted quick release valve to isolate or cross-link as needed.
The second point is that the more air you run, the more the preload of the shocks overcomes thier dampening ability. I'm not sure how this will effect your application, but it is just an observation having used them for 8+ years.
hope this helps!
--------------------
'87 4runner 37x12.50x15 MTRs
SAS, 4.88's, rear+front e-lockers
4x4Him --- Christian 'wheelin
4x4Him National Forum
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by toynado:
wut wuz the before shock?
I went from the Gabriels that were on there when I bought the truck, to the Trailmaster's that came with the lift, to Rancho RS 9000's. I liked the Rancho's the least. I likes these of course because they ride nice and provide the above mentioned benefits.
frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by Wyatt:
What about dampening on road? Don't you get any wierd funky butt-puckering oscillations (yawing)? ![[Wink]](images/icons/wink.gif)
It's been awhile since I had air shocks on my '65 Old Starfire, but I remember it hopped around like a horny bunny. ![[Big Grin]](images/icons/grin.gif)
No, quite the opposite actually. I had a welded carrier in my truck up until last weekend. With the 9000's, it would buck and pitch a lot in a tight corner. With these the dampning got better.
One thing to remember, I backed the t-bars off to get the ride height back where it was. Also, the front is fairly heavy. I do know what you mean on rear shock applications, I've seen 'em get stiff with air shocks as well. Fortunately, that didn't happen here.
Frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by aowRS:
Frank,
I think your explorations are really commendable. I only have one concern with the setup: By relaxing the torsion bars and giving the air shocks some of the support duty, you are stressing two items not originally intended to support the weight of the frontend. While you strengthened the upper shock mount, I would double check the lower mount and possibly reinforce that, if not cannibalize the lower strut mount from a 3rd Gen. These were designed to take the brunt of the suspension duties, while your stock mounts were only spec'd to keep a fairly tame shock in position.
The other item is the shock itself - is it sold more as a "helper shock" for load carrying, or do you think it is up to the task of taking a portion of your frontend weight on a continual basis? I've seen these type shocks used on a friend's off-road project buggy, but the vehicle weighed maybe 500 lbs.
I think the idea is great - I would just strengthen the A-arm areas to mimmic the 3rd Gen. and check whether the shocks are able to cycle in the fashion you describe. I would assume that the majority of people use these to add weight-carrying capacity, and as such, probably lower the pressure when not needed. It would be nice to do away with the rigid T-bars completely.
Just some thoughts.
Andreas
Andreas, good points.
As for the strength, I agree the shock mounts aren't originally intended for load bearing, hence the strengthening of the upper. The lower, however, is by far mostly in compression. At extremes, there is a shear component as well. Whether or not this ever becomes a point of failure remains to be seen, but I can say that I pound my truck really hard and had no problems.
As for load carrying, that's what these shocks do. Many of them will carry 1000lb. I don't think these are that high but that's fine, they don't need to be. They max at like 150psi and I'm running at about 110. You need to air them up from time to time like you would a tire, but carrying load is what they do if there is more air pressure in them then in the outside world. Their longetivity is something that only time will tell.
Frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by Dandeman:
I've been thinking about this for a long time, but plan to soon try the Gabriel air shocks on the rear of my 4Runner and crosslink them... and plan to use as follows.. The rear shock mounts are very beefy, so think they are up to the job.. that can be one of the concerns.
Since I already have an onboard 100psi air compressor I was going to install two electric air control valves for in cab control... one to pressurize, and the other to vent back down..
On road, I would leave them open (so no effect from crosslinking and vehicle will run at normal height) but off road where I really need to improve rear overhang clearance a bit, crank them up.. this is important as on our off roading (aka long trips), the back end is loaded down with extra weight..
not expecting any improvement in rear articulation limits (as limited by design, per investigation by Steve Schafer), but maybe some in range improvement.
hope to start on this soon....
One question elripster, I'm pretty sure I've read you can do this with the Gabriels, but can you confirm whether you can run them with zero air pressure.. I know you can't do this with air bags.. as they will get out of position and get ripped up...
Nice idea, I was thinking of an onboard set up like that down the road.
As for the 0 pressure, these need 30lb min or the airbags inside will get damaged.
Of course, I ripped one of the air lines due to poor routing and wheeled it hard at speed until the shocks got so hot they faded away. I fixed the line and aired right back up, no problems and that was many months ago.
Frnak.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by Lou Bell:
Having had Gabriel air shocks ("highjackers") on my last truck and currently using them on my firewood hauling trailer I would like to make some comments about your application of them.
The first is that when you cross link them, the vehicle behaves more "top heavy". This is a much bigger concern on-road as it can lead to excessive body roll. Off-road, the only problem I see is in off camber situations. The downhill shock will compress, pushing the air into the up-hill shock. Not what you want when on a side hill. You are right in saying you will need a sway bar. This will definately help. I have the shocks on my wood trailer on seperate air circuts now to help negate unwanted roll and side to side pitch on-road. Maybe you could install a cab mounted quick release valve to isolate or cross-link as needed.
The second point is that the more air you run, the more the preload of the shocks overcomes thier dampening ability. I'm not sure how this will effect your application, but it is just an observation having used them for 8+ years.
hope this helps!
As for the top heavy, softer springs would do the same thing. The ability to select the cross linking would be a nice addition to this set up as you would then not have this problem on road.
I view this as an acceptable consequence of moding a vehicle for this type of off road use at least for now. By the way, off road, the added flex makes the truck LESS tippy. This truck is a dialy driven vehicle and the body roll is not appreciable.
Again on the dampning, I haven't noticed a problem. I like the dampning characteristics quite a bit. It settles quickly, the tires seem to do a better job of tracking the surface on the down side of a bump, it's not harsh, it's just kind nice really.
Frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
Before I split for school, you need to put a section of dowl to resize the lower eye to the size of the bolt. I haven't done that and my bushings are all sqirting out. It's not the right way and I'll fix it soon. I'm not sure what size as of yet.
Frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
Harry, do you think this and the LSD post would be good to add to the tech section? If so, what changes would I need to make to the content and/or format? I'm up for it if you think it's a good idea.
Frank
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
Robinhood150
Body Damage is Cool
Reged: 08/28/01
Posts: 1520
Loc: Wandering around Phoenix
|
|
Would it be better to link the front and rear shocks together? That is, link the passenger side shocks together and link the driver side shocks together. This way you use the leverage of the solid axle to apply even more (or less) pressure. Plus, since the rear shocks travel more, you would be applying more pressure on top of that.
To think of it another way, instead of using the front wheels to drive the rear axle down, you're actually using the rear axle to drive the front tires up.
Steve
--------------------
Steve
My Website ||Gettin' off 4wheel drive club member
'93 4Runner V6 4x4 auto tranny
If you have to ask about a SAS, you're not ready for it.
|
elripster
Roll Me Over
Reged: 03/15/01
Posts: 2731
Loc: San Diego, CA, USA
|
|
quote:
Originally posted by Robinhood150:
Would it be better to link the front and rear shocks together? That is, link the passenger side shocks together and link the driver side shocks together. This way you use the leverage of the solid axle to apply even more (or less) pressure. Plus, since the rear shocks travel more, you would be applying more pressure on top of that.
To think of it another way, instead of using the front wheels to drive the rear axle down, you're actually using the rear axle to drive the front tires up.
Steve
I was thinking about that today. It very will might work much better as like you said, more travel out of the rear. When the rear tire compresses, it'll really increase the tendency for the other tire to go down, likewise, when it extends, it will have the same effect allowing the other tire to come up.
Also, while you might have more brake dive, you wouldn't have the body roll component of the linked system.
See, already lots more good ideas!
Frank.
--------------------
1994 4runner, 3.0, auto, 4.88's, 31's, BJ spacers, Coil spacers, air shocks, D-ring anchors, 4Crawler F/R swaybar discos.
www.sdori.com
|
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
