Bkennedy's SAS and Rebuild Thread

[Rick]

Sure is nice floating down the trails with the greatest of ease

 

[BKennedy]

Sure is nice floating down the trails with the greatest of ease

I had never been on that trail before. Its supposed to be a 2+, but was more like a 3+. It is about an hour climb up a steep and narrow trail. Lots of off camber spots, big rocks in the middle of the trail, and ditches. No smooth parts. All on the side of a very steep hill. Nothing really challenging in itself, but technical. You have to plan your lines carefully because some of the time, you are driving with your tires on the edge of the trail. Beautiful view from the top. You have to return the same way due to a locked gate at private property. I don't think I would have tried it solo with the old suspension.

 

[4pullingGM]

Wow! She flexes really well! I'm hoping to get to go on some nice, scenic off road trips. Y'all have much better scenery than Illinois!

 

[Rick]

Y'all have much better scenery than Illinois!

That's why I moved from Illinois to Arizona 30 years ago. Sick of the corn fields!

 

[sirhk100]

I'm not sure I've ever noticed, what's your rear suspension package consist of right now? Looks like the rear works just about every bit as well as the front...

 

[BKennedy]

Rear works well, but not as good as the front. I think they compliment each other to make it a nice, stable ride. If I was going to do the shock mounts over again, and I might, I would not put the rear shocks on so much of an angle. It allows some body roll. Also would like to double sheer the mounts. I did not put together the rear shock mounts. That was done at a friend of mine's shop when I was still paying for stuff. It has held up well over the years, but could use a refresh.

Rear Suspension:
Spring Over Axle (SOA).
Stock leaf springs modified with another cut-down set of stock leaf springs for a total of five leafs per side with no overload leaf.
Superlift SOA brackets (modified for strength and welded to tubes because they broke).
Double shocks (Bilsteins).
Custom shock mounts and cross member.
Detroit locker.

The pic with the leafs is right before I installed them the first time. I pulled them, took out the shims between the leafs, and sprayed each individual leaf with some graphite paint. It was a mess to work with, but they really flex now. Pulling the shims dropped the height about 1/2", which is what I wanted to lower the rear a little.

 

[sirhk100]

LOL, I know all too well about the graphite paint! Between races on the race truck the leafs get torn down, wire wheeled clean and repainted. It's a long tedious boring process... Especially when each leaf pack has 13 leafs! LOL

Simple setup and looks like it flexes great! Can see where the body roll would come into play though for sure. Nice job though!

 

[BKennedy]

Stuff I still need (want) to do:

1) Move exhaust "Y" pipe up a few inches for more ground clearance, and to clear a trans pan skid plate. Fab up skid plate with new forward cross member / support at the bump stops.

2) Refresh rear shock mounts. I am convinced that some of the body roll I get while in the dirt and on the street is due to the shocks angles. There is just nothing in the rear except for the leaf springs to fight the lean. If I move the top mounts outward, I can reduce the angle and still have enough shock travel to get a little more down flex. I need to get under there and figure out the best method of attack. Either using the existing mounts and adding to them, or cutting off the axle / frame mounts and starting over with something like these:
Top / frame mounts; http://www.ruffstuffspecialties.com/catalog/SBRKT-FLT.html
Bottom / axle mounts; http://www.ruffstuffspecialties.com/catalog/SBRKT-CUR.html

3) Fab a new roof rack out of 3/4" EMT. I want a roof rack that covers the entire roof, that is low-profile and sleek, maybe 4" in total height. Just enough room to get a curved LED light bar in between the top and bottom tubes. Looks like I could get a 44" light bar in there. Also could lay the Hi-Lift flat inside the rack. Figure I could sell the current rack with existing lights to pay for the build.

4) Electric fan upgrade. It gets a little warm on the freeway going up long, steep grades. I always end up in the right lane with the big rigs. Went up the back side of Big Bear Mountain last year, which is a long, switch-back type of steep dirt road. Noticed it was getting warm, so its not just the freeway. Planning on using a fan out of an older Volvo. They are thin, put out lots of air, and have a easy to remove relay pack, making it easy to wire. Local Ecology JY is having a 50% off sale the last Sunday of this month. Hopefully, I can get down there and find a fan.

 

[johnny499]

The truck looks great!!!
I have been kicking around a very similar roof rack design for mine. Were you going to add extra mounts towards the windshield or let it float? I would suggest using tubing instead of EMT, the galvanizing and thin wall combination make it a pain to weld and paint does not love to stick to it either. I do get the appeal of the price and availability but hate the prep so you can weld it.

 

[BKennedy]

I was thinking of removing the stock roof rack sliders entirely to get the new rack to fit more flush with the roof and adding new mounts to the front. Just going to plug / seal the original rivet holes that don't line up for mounts. I never liked the way the sliders are mounted to the roof, and the rivets are getting loose due to all the body flex. Only problem is dropping the head liner to get nuts under it is going to be difficult because the roll cage is pushed up against it, so might need to use rubber nuts from the outside.

EMT is what I am going to use when I get around to it. It works great, very rigid when properly supported, is cheap, and light weight, with the only drawback being paint not sticking to it. If you roughen the finish up with emery cloth, paint sticks just fine. I have used it before for a large canopy over the RV where I had to weld pieces together. Welded fine, painted fine, no real problems.

The roof rack probably won't happen for a while. It's basically cosmetic since I rarely use the one I have. Need to get the other stuff done first, and I have some water saving landscaping projects around the house to do as well.

 

[BKennedy]

Rear shocks:

Just spent an hour under there measuring and trying to figure out if I can use some of the existing mounts when I redo the shocks. Nope.
The 2x2" cross bar is not sitting level, so all the mounts are about 3/4" higher on the passenger side. I guess when the guy I paid to put it in several years ago did it, he did not take into account the frame heights on each side. So, after measuring, it was obvious that the shocks are extended about an inch more on the passenger side than the driver side at ride height. I am going to order the Ruff Stuff mounts, cut off all the old stuff on the axle and weld them on. Then slap the other mounts to the side of the cross bar and weld them in place so I don't have to try and get that cross bar out (it is really welded in there).

 

[BKennedy]

Okay, lets talk shocks!

My current rear dual shock set-up is like this

It needs a re-do, as mentioned above. The axle mounts I think I have figured out. I ordered these from Ruff Stuff;
Axle Mounts;


Frame mounts:


I can use them in all sorts of ways. The frame cross mount is slightly behind the rear axle (about 2"). I have a few questions.
Should I just put them straight up and down, or angle them in at the top (straight up and down requires moving exhaust pipe, so I would rather angle them inward)?
Why are so many off road vehicle's rear shocks mounted so they lean towards the rear of the vehicle at the top mount?
Should I keep both shocks per side on the same angle / plane?

 

[Kirby N.]

The more straight the more efficient they are. The closer to the wheel the more efficient they are. Efficiency is measured by the amount of movement of the shock in relation to the amount of movement in the wheel. If it is 1:1, the shock will be dampening best and the wheel will not have mechanical advantage on it. If it goes to like 1:2, because of angle of shock or shock is in a foot from the wheel, then the wheel has an advantage on the shock and the shock cannot do its job as well. You need a shock valved twice as stiff to get the same dampening. Not to mention the heat and strain placed on the shock that will on contribute to fading. Most vehicles cannot get the shock vertical due to space constraints- a long enough shock to get the up and down travel required cannot be place in the space (in order to get a 12" travel shock, you need to be able to compress is at least 14" and extend up to at least 26", so often there isn't 14" of space on full compression. This is why a compromises are made, stiffer shocks at angles. Also sometimes shocks are mounted behind or in front of the axle at and angle or both on opposing sides to aid with axle wrap on leaf setups.

 

[Kirby N.]

Also, the bushings will help with the movement of the mounts during compression, but I would try to keep the upper and lower in sync with each other and perpendicular to the shock. Otherwise you will accelerate bushing wear.

 

[Kirby N.]

With the efficiency idea in mind, when you think about how little your shocks would move in your current setup especially in cases of body roll when on side would compress and the other side doesn't extend much like in high speed cornering, 1 shock mounted more efficiently would be much more effective.
If I were setting up those shocks I would take off what you have and measure them extended and compressed. Then I would go cycle the suspension to full stuff on one side and full droop on the other and with a tape measure and the mounts in hand figure out where I could mount them with them as vertical and outboard and lower mounts tucked up realizing that you will have to compromise on all of those unless you chop holes in your floor.

 

[BKennedy]

Thanks.
I measured it all out a few weeks ago, and I know how much shock shaft I need showing at ride height with them angled in slightly (4"), to get the most out of them. I was looking at pictures of a stock Explorer's rear axle, and I think I can get close to the original angles, but come off the lower half of the axle to protect the shocks. Biggest issue I can see already will be keeping the shocks close together on the axle, but not having them contact each other. I saw some pics on the interweb that showed mounts like mine with a spacer in between and one long bolt for both shocks. I think I can make that work, but the mounts will have to be angled on the axle and at the top to save the bushings. Also noticed that the shocks I have use 1/2" bolts on top mounts and 12mm on the bottom. Need to press out the old sleeves for the bottom mounts and get some 1/2" sleeves in there to match the mounts.

My goal with the Explorer is to have an all around off-roader that does every type of dirt well. I am still surprised when I take it out how well balanced it is, and how it seems to be almost exactly what I was shooting for when I started. I thought when I did the SAS I would lose some of the go-fast type wheelin' capability, but it seems the opposite. The only thing it doesn't do well is go up long, steep grades on the freeway. Tends to get a little warm. I edited the post 789 to add an electric fan upgrade.

Really, I could wheel it as it for many happy years, but what would be the fun in that?? Looking at the rest of the Expo, the rear shock mounts look a little ghetto, and I know they will eventually fail.

 

[Kirby N.]

I wouldn't worry too much about the original angles. Ford mounted them with lots of compromises due to constraints of a stock exploder that no longer exist in yours. Mainly ride height and spare tire location. I would try to put the uppers on the frame if I were you, straight back at the angle you need to get all the travel. Not in on top so you don't have to fuss with working another angle. Strong and efficient.

 

[BKennedy]

I wouldn't worry too much about the original angles. Ford mounted them with lots of compromises due to constraints of a stock exploder that no longer exist in yours. Mainly ride height and spare tire location. I would try to put the uppers on the frame if I were you, straight back at the angle you need to get all the travel. Not in on top so you don't have to fuss with working another angle. Strong and efficient.

Looks like I will be rerouting the exhaust then. It would be a lot easier to mount at 90* to the axle and angled rearwards towards the top, except for the exhaust. Seems like everything I do makes me move or redo something that was done before.

 

[Rick]

The Zen and the Art of "Explorer" Maintenance

I know the mechanics of the modification perpetual motion machine all to well.

 

[BKennedy]

No kidding.

If I am going to do it over, I am going to do it right.
If I get time Friday, I will take the Explorer to DualTone Muffler. I have been going to them for years. They are honest, and fairly priced. See how cheap I can get the "Y" pipe moved up and the rear section rerouted.

Here is a pic on the interweb I found that is similar to what I am planning. I would want the shocks a little closer together, much stronger, and outboard as much as possible on the axle. I think this builder went in so far to stay inside the frame rails. Have you ever done a search for pics of dual rear shock mounts? Had to sift through a ghetto hack job bunch of crap to find this one. Even this pic has some serious ghetto, look at the lift blocks and that exhaust is all over the place.