One Piece at a Time: My 1985 Diesel Suburban

[AgDieseler]

Early weld sesh’ to finish the cans.

Great application for chill blocks.



Coffee is empty, so I must be done.


I rooted most of these at 130 with a small bead and copper backer. It’s a fully penetrated weld that doesn’t eat the edges.


I follow up with a pulse (machine or pedal, just depends on what’s setup at the moment) and fill the profile. Chill blocks and backers are vital to maintain a steady puddle and with good wetting, and therefore a consistent profile.




There are many ways to accomplish these welds. That’s just my method.

David

 

[AgDieseler]

With the rear suspension at full stuff, now is a good time to mock-up shocks and the swaybar.

Lightly modified swaybar saddles.



After a bit of measuring, it turns out that the upper shock location is right about where the swaybar mount sleeve wants to reside, so that sleeve is going to serve double duty as the upper mount for the shocks. It’s all 1.75 DOM, and looks like it might just click together.

David

 

[AgDieseler]

The swaybar and upper shock mounts will have to be separate. There is so much droop in the rear packs that the arms and links need a lower pivot point on the frame.

This location was not intuitive, but it’s going to work just right. It clears the shocks, and the arms need only a minor trim to clear the bump cans. Any farther forward or up, and I’d have to think hard about frenching this whole thing into the frame.


2-1/4” driveshaft clearance at full bump. There are larger problems if these two go conjugal.


I built a recess Into the can mount, so the end link can be as vertical as possible.


Lots of fitting and checking. Stephen talked me out of putting the swaybar in the fuel skid. Apparently, the suburban is not a prerunner

David

 

[kgblazerfive]

Is there any reason not to put it in the frame ? Seems like it may be simpler.

 

[AgDieseler]

Is there any reason not to put it in the frame ? Seems like it may be simpler.

Like, through the face of frame? I don’t think that would be much simpler, but it could be very much preferred in applications that are lower than my truck. It would get the bar closer to the COG of the truck, which is somewhere around the crankshaft on big junk like this.

David

 

[kgblazerfive]

Yeah like drill a hole the size of the tube on both sides put in tube and weld away. Would get it a bit further from the driveshaft.

 

[AgDieseler]

Yeah like drill a hole the size of the tube on both sides put in tube and weld away. Would get it a bit further from the driveshaft.

Yeah. We’re talking about the same thing. That’s a play if you need the bar in that spot - low lift with massive down travel. I’d still think that an inner brace or boxing plate would be smart to avoid working the frame face at that one weld. This clearance is adequate for my purposes, but after looking at these photos, you’ve inspired me to shave another inch or so from those small pedestals.

David

 

[jkroberts]

That should work good. I've run a swaybar pretty much the exact same way with great results on multiple rigs. It also looks like there is room to run a piece of tube between the bottoms of the bumpstop cans. That would help a lot with making sure the frame doesn't peel out! Maybe I missed it but what is the size of the swaybar you are using?

 

[Greg72]

Yeah. We’re talking about the same thing. That’s a play if you need the bar in that spot - low lift with massive down travel. I’d still think that an inner brace or boxing plate would be smart to avoid working the frame face at that one weld. This clearance is adequate for my purposes, but after looking at these photos, you’ve inspired me to shave another inch or so from those small pedestals.

David

....and if that doesn't fully get you there, you can notch the driveshaft.

Or if you want a serious suggestion, you always have the last resort of lengthening the slip on the driveshaft and moving that large tube diameter out from under the new swaybar mount. That's probably good for another 1 - 1.5" if you really needed it (which it doesn't appear that you do)


-G

 

[AgDieseler]

That should work good. I've run a swaybar pretty much the exact same way with great results on multiple rigs. It also looks like there is room to run a piece of tube between the bottoms of the bumpstop cans. That would help a lot with making sure the frame doesn't peel out! Maybe I missed it but what is the size of the swaybar you are using?

Glad I’m running down some well worn tracks.

I’m definitely tying together the rails at the bumps, and will tie that into some more general bracing for the rear suspension. Tying the relocated front hangers, factory crossmember, shock bar, bump crossmember, tied together at one level or another is the start of my general chassis rigidity update. That bracing plan will carry forward in the frame - planning for a basic X brace.

...you always have the last resort of lengthening the slip on the driveshaft and moving that large tube diameter out from under the new swaybar mount. That's probably good for another 1 - 1.5" if you really needed it (which it doesn't appear that you do)

You're looking at the same thing I am. These springs allow for a greater deal of bump travel, so the driveshaft does actually have to get a bit shorter. But, there's a whole smash load more droop, so the spline engagement will also lengthen.

David

 

[AgDieseler]

Maybe I missed it but what is the size of the swaybar you are using?

Sorry. It’s the 1-1/4”x37” hollow speedway bar that ORD has in their kit. Seems pretty universal and easily adjustable.

David

 

[AgDieseler]

Finished up the shock and swaybar crossmembers.





Here’s a fast look at the separate root and cover passes. I’m not adept enough to get the right profile in a single pass, so a cover lets me dial that in just right. When we see neatly stacked dimes - like a Geiser chassis or Kibbetech upright - it’s usually a cover pass.

Root is straight current 130-135A, with the torch angle favoring the 3/16.



The cover is a programmed pulse, 180A, 50% on, 20% background, and 0.9 Hz. You can lower the heat input, increase the duration and weave to smooth, or like this method, go for hot and fast. I prefer to minimize heat input with a hot and fast approach.



David

 

[AgDieseler]

Got the rear shock brackets 90% dialed, and just need to make a few tweaks to the axle side mounts.





David

 

[mrk5]

I was half expecting to see a cantilever shock setup.

 

[Greg72]

Those rear ORD springs may be nice a soft, but those shocks you are using are going to punish your kidneys.


-G

 

[AgDieseler]

I was half expecting to see a cantilever shock setup.

I’m working hard to keep this half simple...er.

Those rear ORD springs may be nice a soft, but those shocks you are using are going to punish your kidneys.

It’s the latest in magnetic fixed valve technology.

David

 

[AgDieseler]

Today was a cleanup and reorg day. I needed a big reset before the final assembly push on the rear suspension.



David

 

[dbcorvairracer]

Today was a cleanup and reorg day. I needed a big reset before the final assembly push on the rear suspension.

View attachment 365001

David

I love doing a reset. On big involved projects it's too easy to roll from one thing into the next and things get gradually more and more difficult. I just did this after doing a bunch of plumbing, electrical, insulation and drywall in my garage, well worth the time before moving onto the next section. I forget sometimes that you aren't working in a huge shop with all you have going on sometimes it seems like you must be working in a 40'x40' or bigger shop.

 

[AgDieseler]

I forget sometimes that you aren't working in a huge shop with all you have going on sometimes it seems like you must be working in a 40'x40' or bigger shop.

Just the 576 square feet my wife and I built just over a decade ago. Very few things are not on casters.

David

 

[AgDieseler]

I need to get a mill, but a bandsaw and sander will do on a pinch.

I’m down to getting the swaybar nestled between the rail and the pack with some room to twist. Double shear, single position. I’ll make an adjustable arm later.





David