No Limit Trailing Arm Rear Suspension

[robnolimit]

We have had so many ask about this, and it was a tough call in some ways to go ahead with this project. I would like to explain that. At No Limit, we are focused on performance suspension. We have never claimed to build the lowest, the 'showy-est' or the lowest price. We focus on the best ride and handling. There are other great builders of the lowest ride, and you should steer clear of the low price crap.

We have the FatBar 4-bar rear for C10's, and it's great. Ask anyone running one. Smitty proved it's ability beyond any doubt. We have the custom 3-link, like the one Wes D. runs and it's a short course killer. Now both of these are great, but they do require welding and fitting, and the three link must use a Ford 9". Then we have a shock mount kit, panhard kit and sway bar for OE C10 rear suspensions as bolt-on upgrades. These work very well to enhance the original truck, but there are some shortcomings.

We also took the time to study what others are offering, as there isn't really any reason to duplicate something that's already available. The big problems are as follows; 1)Limited travel forcing a stiff ride, mostly due to short shocks and poor location. 2)Rigid, fixed front bushings that limit the axle articulation - OE arms twist, tubular arms don't. 3) High roll center that limits the side bite available, forcing the truck to be 'loose'. 4) Limited clearance for exhaust. With this in mind, the goal was to produce a bolt-in kit with none of the shortcomings of the current marketplace.

[robnolimit]

So, there is a picture of the new C10 kit. We have already done a production run and a bunch of driving/testing, and we are very happy with the results. Ride quality is great, handling response is even better. The full installation can be done in less than a day. I'm going to use this section to lay out the install, and also to 'build' the instruction pack. So, your feedback will help. Thanks in advance.

The kit includes everything seen here, and there are only a few upgrades or mods available. Complete kit $1395.00

1 pair trailing arms LH/RH, with poly lined Monster balls. Pinion angle corrected
1 pair front adjustable trailing arm mounts. Anti-squat corrected
1 pair upper coil-over mounts. LH/RH
1 Low-Roll adjustable panhard rod kit
1 pair 7" travel coil-over shocks
1 pair 14" springs - 225 lb base rate.
3 hardware packs. Trailing arms, Panhard rod, coil-over

The standard kit will include Viking double adjustable shocks and 14" 225 lb springs.

Upgrades/mods:
RideTech Single adjustable HQ shock + 125.00
Ridetech Triple adjustable TQ shock + $700.00
RideTech Single adjustable SHockwaves HQ + $525.00
Ridetech Triple adjustable Shockwaves TQ + $1225.00
Mod spring rate, 200, 250, 275, 300 No Charge.



Here is our install test mule. Nice clean LS powered C10. This truck had some parts on it already, but it wasn't delivering the ride quality or the handling that the owner was looking for. Most of these parts were removed and sold. Some we are going to re-use.

[robnolimit]

This truck already had a bolt-in notch. Now, lets talk about that. Shame on the aftermarket. Shame on them for helping you cut into your truck for no reason. ??? OK, the frame is approximately 4" tall (rail height), keep that in mind. Also, the rear gear housing is about 4" above the top of the axle tube. (top of center chunk to top of axle tube. So, if you pull the bump stops, and the axle travels up to hit the bottom of the frame, the top of the center section (gear housing) is even with the top of the frame. Are you with me so far? Now realize that the OE bed floor is .75" above the top of the frame. (Or worse, even with it if it's a wood floor). So, if the axle travels up more than 3/4" into the notch, WHAMMO, it hits the bed floor. So, if your keeping the OE bed floor, a 1" notch with a side mounted bump stop is all you need, and you wouldn't cut the frame so much.OK, I know some of you want it lower, and will cut a hole in the bed floor, but that's not what we're doing here. Please think about the notch thing before you cut.

We are working on a notch kit with bump-stops included, but the forming match may take another two months. We are not going to include bolt-in C notches with this kit. We will have them available separately. But, sincle so many trucks are already notched, we are not going to force you to buy something that you don't need, or don't want.

[robnolimit]

Step 1. Get dirty and noisy. You need to remove the OE front trailing arm mounts. There are six rivets in each. Drill, cut, burn.... however you like. I like to use a scarfing tip on a torch, but most will find it fairly easy to center punch the rivet, first drill all the way though with a 1/4" bit, then use a 7/16" or 1/2" bit to cut the head off. Once the bracket is, grind the rivet shanks smooth and punch them out. The new front mounts bolt into the same holes. We provide two extra holes that you can drill and bolt in as well. All hardware is provided.

[robnolimit]

The new trailing arms go in next. This truck is kind-of low. It had 2" blocks under the housing, and to keep the shock as long as we wanted, we are keeping the blocks. The trailing arms are adjustable in length. This adjustment is used to set the wheelbase and to square the axle in the chassis. In the long run you may drop the arms a few times to get it perfect. No big deal, it's like carb jetting, with really big parts. The arms bolt in just like stock with new hardware provided up front. Use anti-seize on the threads, and the OE U-bolts for mounting the axle.

[robnolimit]

Next up comes the upper coil-over mount. Once again, it's time to cut rivets. On the side of the frame, just in front of the OE coil spring mount there are three rivets. You need to remove the rear two. Same as before, but again, be careful not to damage the rivet holes, as you will use them again.

One the two rivet are out, drill out the two holes to 3/8". Then bolt the coil-over bracket in place with the supplied hardware in these two holes.

[robnolimit]

Now it's drill time. Use a 3/8" drill to drill out the rear hole for mounting the coil-over bracket. Then use 1 5/8" bit to drill through the frame for the upper coil-over mount bolt. Put the third mount bolt in place.

TIP: For the 5/8" hole, start with a 5/8" bit, using the bracket as a guide to center the drill. Stop after about 20 seconds. You should have the beginning od a hole started, in the center. Switch to a 1/4" bit and drill out a pilot hole, using the center from the 5/8" bit. Then go back to the 5/8" bit and open the hole up. This is much easier than fighting with the 5/8" bit all the way though.

*** Note the poition of the gusset on the mounting bracket. It is to the rear of the truck. There are 'left' and 'right' hand brackets. ***

[robnolimit]

More rivets. - But these are the last ones. Remove the OE panhard mount bracket. Please take note that some of the rivets are also holding the frame and the crossmember together. You can A) drill them out to 3/8" and use the hardware provided to bolt them back together. B) Weld the crossmember - Yes, we said it is a full bolt in kit, but some of you will ask. So, If you can weld (really weld) and you are tired of drilling, yes, you can weld it. C) Leave a portion of the rivet in place to hold the crossmember. I wouldn't recommend this, but, I'm not your mom. But really, go back to option A. The new mount doesn't use any of these holes.

[robnolimit]

The new Panhard mount uses this hole to locate it. Chase it with the 3/8" drill bit and bolt the new bracket in place. There are two mounting rails for the panhard rod on the inside of the bracket. They should be at 90 degrees to the frame rail flats. Or, if the truck is level front to back, these mount rails should be straight up and down. Notice that the bracket fits the frame profile nicely when it is in it's proper location.

[robnolimit]

There is only one hole left to drill. This is for the panhard bracket brace. To get the roll center low, really low, compared to a stock or modified C10, the mounting brackets have to drop down pretty far. Even though the new Low Roll mount is made from 1/4" steel, it would bend in an instant if not supported. The support rod is 1" in diameter and uses 1/2" heim ends. They are both RH thread. Simply assemble the bar with 3/8" of thread exposed on the rod ends, and bolt it into the new Low Roll bracket. The other end will bolt to the bottom of the crossmember. Use the brace rod to locate and drill the 1/2" hole. Bolt in the brace rod.

[robnolimit]

Now you can bolt in the new panhard rod. This has a RH and a LH rod end. The hex end of the bar has RH threads. This makes adjustment easier without needing to unbolt the bar to adjust the rear axle center. To start with try the center hole on the Chassis side and the top hole on the trailing arm side. Once the bed is back on you can set the bar. The goal is to try to keep it a level as possible for neutral handling.

[robnolimit]

Now you can prep the shocks. Bearing mounted coil-overs often need the bearings installed. You will need some snap ring pliers and Loctite. (red or blue is OK) Install one snap ring, the coat the bearing outer surface with Loctite. I like to coat the bearings and let the sit a while. 10 minutes is good. Slide the bearing in place and put in the second snap ring. Install the other bearings the same way.

[robnolimit]

Next, go get some anti-seize. Not grease or oil , go get some anti-seize. Coat the top 3" or so of the shock threads. You can clean up the excess later, but doing this will make ride height adjustments a LOT easier. Then assemble the springs and adjusters onto the shocks.

[PGSigns]

Nice looking setup. Well thought out.
Jimmy

[Sean1985]

I like it. And interested.

[Andy4639]

Rob looks like another great product from you.

[robnolimit]

Thanks for the feedback. I stopped last night after looking at the posts, I need to go into a little more depth.

[robnolimit]

Panhard Rod Info

We call this a "Low Roll" Panhard rod, because of it's ability to lower the Roll Center of the truck. You need to know that doing this may actually increase the amount of body roll in a given corner (all other factors being equal, compared to a higher roll center). So, along with this we have spaced the shock/spring assembly farther outboard to combat/control the extra roll forces.

We have to start out understanding how tough it is to get trucks to handle great. High CG, Low rear weight %, and a high % of rear unsprung weight, are the three performance killers in the average truck. So, taking the sports car route of "low body roll" - flat corners, isn't going to work so well. We can use the body roll forces to basically stuff the outside rear tire into the pavement, and hold the truck down through the corner. Most trucks would notice a net reduction in body roll with this suspension system, as compared to a stock set up, but it is not a 'stiff', 'flat', low travel design. That kind of thing hes been proven to be less effective.

Here are a few more picts of the installed Panhard bar on our project truck

[robnolimit]

Shocks and Shock Placement

I'm sure you noticed that we chose a somewhat 'Out-of-the-box' location to mount the Coil-overs. This location does offer some advantages. A wider spring stance is a huge gain over conventional locations. Increased clearance for exhaust is another. Even in this outboard location, this truck still has plenty of room for a 12" wide wheel and a 335 tire. The last big advantage is the gain in suspension travel. By leveraging the shock and spring (mounting the lower coil-over ahead of the axle) we gain suspension travel as a % of the shock travel (based on the leverage % and the length of shock travel available). This forward location also allows a much longer shock to be put into place.

This new system uses a 7" stroke coil-over, or Shockwave, and a 14" spring. That's borderline Off-Road travel specs. By leveraging the shock, we can get an amazing 8.6" of actual wheel travel. The leverage is a plus in reducing the effectiveness of the shocks compression valving (needed in off balance trucks), and we simply do some math to calculate the spring rates need to work with the increased loads on the springs.

Base Shock The base shock included with this system is the Viking Crusader double adjustable shock. This is a non gas charged shock. They have a very smooth, and very soft (at low setting) compression valving, and the rebound is adjustable to tie down and control the truck in normal and performance driving. The is a great pick for cruisers, drivers and occasional Auto-x'ers.

Upgrades Those demanding more performance can choose RideTech single adjustable HQ series shocks. These are gas charged monotube shocks with adjustable rebound. The valve curves are a little steeper and the compression valve is pre-set to our specs. A great choice for weekend track events and more aggressive driving.
Next is RideTech's all out Triple adjustable TQ series shock. Tons of valve technologie to deliver the absolute best in all situations. From the softest, smoothest ride on all weather tires, to the firmest, fastest reacting control for lo-pro sticky's for a day out at the local road coarse or Auto-x, these are the ticket.
And for the Air Ride guys, we simply swap out the coil-overs in favor of RideTech 8000 series Shockwaves (7" stroke) in either single (HQ) or triple (TQ) series shocks.

[robnolimit]

Mounting the coil-overs is a simple bolt-on, once the upper mounts and new trailing arms are in place. We have chosen to use all bearing mounted shocks and Shockwaves for this system, The bearings offer free movement and articulation, and there is no worry about 'chatter' or road noise. These parts are just plain better quality than those of twenty years ago that started all the bad rumors. 5/8" grade 8 bolts are used top and bottom. Torque to 60 ft/lbs.

[robnolimit]

More Shock Tech No, this shock is not mounted upside down. Time for shock history 101. Most shock knowledge is based on what we've seen in the past, and that's mostly working on mass production cars. Yes, the Big-3 (and all others) know that the ride quality and performance would be better if they reduced un-sprung weight by properly mounting the shocks, but, they are a few more factors at work. MONEY is #1. Simple hydrolic shocks are not built well enough to run 'upside down', they would cavitate, heat, froth, and then leak out all over the place. So, to save $$, in goes the budget shock. I once heard that GM paid less than $4.00 for basic tube shocks. Besides, Most drivers don't really care (sad, but true) about the shock quality that much, so, barely good enough is OK with them. But, not for use. "Good enough" isn't even gettin gup to the starting line. We want 'Better', 'Best'. 'Awesome',...... So, we start with a great shock and only go UP from there, and they mount the correct way, to reduce un-sprung weight. - Every little bit helps, and the details matter.

[robnolimit]

Sway Bars As we stated earlier, to get the truck to really grip the road, the low roll center and using the roll force to plant the tire is the key. But, we don't want to have excess body roll. The wide spaced spring stance shoule handle that just fine. But, some of you will want more. Rear sway bars are effective suspension tools that can be used to tune and custom tailor the ride to your liking. Our original design idea was to use a 'floating' bar and links, mounted to the chassis (again, reduction of un-sprung weight) and use links to connect to the trailing arms in a leveraged location. This will somewhat reduce to bars effectiveness, and allow the truck to 'settle in' to the corners with more tire grip. ** Every part of the design so far has been to 'free-up' the axles ability to 'tip' and settle the forces to the road, helping to keep both tires stuck to the road. We don't want to start binding it up now.

This truck had a bunch of parts all ready on it. One of those items was a Hotchkis Suspension floating sway bar. Not a bad design, and almost exactly where we had planned our bar location. - If you check out our rear bar for OE C10's, it's in the same area. So, for the sake of the customer, we decided to re-use the Hotchkis bar. The links were adjusted and it bolts to the trailing arm in the provided mount lugs. The Hotchkis Bar is 3/4" solid. Our plans call for a 1" x .120 wall bar. The twist rates are almost the same. To us, the larger bushing mount surface of the 1" bar is a plus.

*** We will report back on the driver feeling, bar vs. no bar ***

[robnolimit]

At this point all that was left was to put the truck back together. Exhaust, fuel tank and tires. Here's something I'd like to point out.
** We never removed the rear axle.
** The driveshaft was not pulled from the trans
** The brake lines were not disconnected
These things all add up to make the install easier and faster. Without compromising the ride quality or performance of the suspension system. Next week we will have picts with the bed on, the stance, and some road feedback.

[chevy_mike]

Very nice Rob. I am happy someone has taken the time to help explain how the trailing arms should work. It drives me nuts to see folks put poly bushings in the arms or used boxed arms without any type of flex joint up front. The stock I beam design was made to twist, to help with articulation. The rubber joints have some flex as well. When you take all of this factory designed stuff away, all you do is make the arms bind up, which people take for "better handling".

Thanks for helps to educate the masses. Looks like a great setup!

[Clndesl]

This kit is exactly what I was wanting. Wish you would have had it 6 months ago cause now I have a bunch of new stuff I need to sell to get this