I wanted a low C.O.G. solid axle conversion on my '01 Tahoe that stayed 6 lug, retained ABS and auto 4wd. The whole "covid-can't go anywhere" thing made me want to go for it. Should i do a build thread? I started tearing it apart 2 weekends ago. Here's about as far as I've gotten doing it in...
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The idea is to do a solid axle conversion on my 2001 Tahoe. We use the Tahoe for dirt road camping, It needed new tires, and we wanted to go with bigger tires. And bigger tires means a little lift too.
The victim:
I found an axle that seemed to be a good enough candidate. An 8 lug Dana 44 from a '90s dodge, it was for sale for $100, but the guy kept jerking me around on when he would be available, and to apologize he gave it to me for $50.
I knew the outers were different than the standard Dana 44s. This one had a broken u-joint which i didn't care. I originally planned to cut off the inner Cs and weld on standard Dana 44 inner Cs. And then use standard D44 outers so that was no problem.
I picked it up and brought it home and as I stared at it in the driveway i though "hey, that looks similar to the chevy unit bearing..."
So I grabbed my trusty harbor freight digital caliper, and started measuring. And every single measurement kept coming out to within a couple of thousandths here or there. The mounting bolt spacing, the diameter where it slides into the knuckle, the distance from mounting flange to u-Joint...all of it. They both use the same 33spline axle, with the same diameter shoulder at the base of the splines. The Chevy's shoulder is a touch taller so the hub is machined about 0.100" deeper for the shoulder. So the dodge axle fits the chevy, But the Chevy axle in the dodge doesn't quite bottom out.
Next came getting some hubs and actually trying it. It totally worked
So at this point I'm all in on seeing how easy this will actually be.
So I head to the Junkyard, with a tape measure. And it looks like the dodge frame rails are 1/2" wider than the Chevy at the coil spring mounts. I planned to plate the frame after cutting off all the IFS stuff, and so that would easily make up the 1/4" per side that I needed. Plus the Dodge uses a simple shock mounting that meant one less thing to weld on the frame.
But junkyards won't let you bring in anything that throws sparks, so using my cordless grinder to cut off the dodge coil mounts was nixxed before I got through the door. That only left my Sawzall. the only way to use a sawzall was to cut the whole frame all the way through, and take those chunks home to cut the brackets off. It took a couple hours and I destroyed the front half of that truck lol.
The Idea was to use chevy 6 lug brake rotors, I measured, and there was no way to re-drill either the 5 lug, or 8 lug dodge ones and have it work.
But the chevy rotors have a very different offset, and 305mm diameter verses the dodge 295mm. And the dodge caliper bracket was cast into the knuckle, so spacing the caliper out to be centered on the chevy rotor wouldn't work.
But as I looked around the 2000-2001 ram D44 used a 307mm rotor, and those knuckles used a bolt-on caliper bracket.
I figured 1mm per side difference would work, and being bolt on would allow me to space out the caliper as needed using spacers. So I went to the junkyard and pulled 2000 knuckles, calipers, and brackets.
I take the factory dodge Control arm mounting holes and weld on chromoly weld washers to prevent wallowing.
I left the old ball joints in, to protect the holes, and capped off the axle tubes with expansion plugs, and vent tubes.
And then sent all the parts off to be sandblasted. I know that seems a bit premature, but I was going covid-stir crazy and the tahoe was still being driven nearly daily. So this was all i could do to keep busy
Then came the tahoe to go under the knife, took out all the IFS stuff.
I had the coils sandblasted too, and then painted them with red POR15 caliper paint.
I then set the weight of the vehicle on the springs overnight to measure the sag they'll have under its weight, and that would help me calculate the fabrication better
When I called WFO Concepts for a pitman arm, they informed me that they also have frame plates for the half-ton tucks. they were only $125, so I went for them.
it involved not only grinding off the IFS stuff, but a rectangular tube on the passenger side that stuck out and was welded. Its the motor mount, and I thought that grinding the weld off that was not ideal. So once I ground it flat, I went in with a grinder, and beveled it, and stitched the thin 1/16" rectangle tube back to the frame rail.
There was also a big bulge forward of the motor mount. That bulge was going to interfere, so I cut it off, slipped some 3/16" inside the frame and welded it up to be flat.
A bit of boring measuring, and using angle finders to get the coil buckets where they need to be.
Some mocking of the axle into the truck.
The calipers were sandblasted too, so I coated the brake calipers in red POR15 caliper paint too.
Then came the moment of truth, tes fitting the calipers on the chevy hub, and rotors. I started with a 3/8" thik spacer on the caliper. it was close, but I'll have some machined that will center the caliper perfectly.
Then came the steering and track bar.
I ordered the Barnes 4wd knuckle over Y steering kit, and their inside the frame track bar bracket.
Knowing the height of the springs under the weight of the vehicle, I could translate that to ride height. Which I replicated using eye bolts in place of the upper shock and ratchet straps.
At ride height the drag link is at a 10.01 degree angle.
pure dumb luck that the track bar bracket fit snugly between the motor mount and the IFS diff mount bracket. which gave a lot of strength by welding it to those two things, not just the frame. I also cut down the bracket to clear the diff.
running a string between the diff side track bar bolt, and the frame side showed a 10.00 degree angle at ride height.
So being within one one-hundredth of a degree is about as close as I could be to prevent bump steer.
It needed a track bar that was bent in such a way to clear the diff cover tightly. And it needed a 1.60" wide joint at one end. The Steinjaeger Jeep JK track bar was one of the only ones that actually shaped around the diff cover rather than just a kink or single bend. It also had a 1.60 joint, and as a plus it is double adjustable so you don't need to unbolt it to adjust it. It was too long on frame side, and too short on the axle side. plus the frame bracket needed a 2.00" wide joint. So I cut it, put a Heim on the frame side, and then sleeved the diff side, and lengthened it with DOM tube and a threaded weld in bung.
I have many more pics, but this is a pretty good start to a build thread. And that gets me pretty much up to date on where I'm at. literally 14 days ago this was a driving car. And i'm only able to work on it after work a couple nights a week, and saturdays.
This is working out pretty good. The Dodge caliper is a dual 2-1/8 piston caliper. The Tahoe caliper is a dual 2.00" caliper. So an upgrade there.
The fact that it's Dana 44 rather than Dana 60 helps it tuck up into the frame tighter. So I can keep it low center of gravity
It already had coil buckets, shock mounts, track bar mounts, and control arm mounts so that saved tons of time.
The chevy hubs literally bolt in as if they were designed for it. That part is so perfect that at some point dodge and Chevy had to have compared notes.
I really like using new stuff, I wanted to use new bolts to hold the hub in. I had to use the dodge ones because the Chevy bolts are too short. The bolt supply house doesn't have a hardened equivalent. And Dodge does still offer them....for over $30 each. And so I'm just going to have to deal with having 6 rusted hub bolts rather than spend nearly $200 on bolts.
I don't want the control arms to hang below the frame. That's needless loss of ground clearance. Plus this is already going to be pretty low to the ground. So hanging something 3" below the frame seemed like a bad idea.
For example, this pic is of a similar setup on a '90s dodge. Not my pic (it's from WFO's site). But you can see how low the brackets hang below the frame.
Proper radius arm design dictates that the rear arm pivot point is longitudinally in line with the U joint on the transfer case. And vertically the same distance down from the u joint center as the mount on the axle side is down from the pinion.
That puts the brackets landing in the trans cross member. The axle brackets are turned inward 10 or so degrees.
Here's a basic preliminary look using tape to see what it'll look like
So we bolted a square tube in, and used it to mark how the brackets need to be angled to have perfectly straight joints at ride height.
Next will be to take the cross member out, Fab the mounts in at what turned out to be a 9 degree angle. And then figure out how to shorten and attach the cross member again. The brackets should not hang down At all.
The pinion on the diff is 2-11/16 above the LCA bolt. So to be perfect my frame side LCA bolt needs to be 2-11/16 down from the t-case u joint center.
And front-to-back it'll need to line up with the u-joint center too.
For simplicity of fabrication I'll probably compromise a quarter inch or so vertically. And to clear the links in the brackets better, i might compromise an inch or so longitudinally.
But i'll have inches of wiggle with how I'm doing my front output shaft u joint location.
Either way I'll have to decide if I'd rather have 100% perfect radius arm geometry. Or a front shaft that's a couple inches longer.
There are benefits both ways, I'm going back and forth on it.
First, does anyone know for sure if the 2001 is one that the t-case has the front shaft spin at all times?
Also it's convenient that I'm able to keep it 6 lug. I have 5 full sets of wheels for it.
(1) set of 15" wheels (no idea if it'll even clear these brakes
(1) set of 16" wheels that didn't technically "clear" the front calipers. But gently grazed them until they wore themselves clear
And (3) sets of 17" wheels one set of stock Silverado steelies, one set of stock Silverado steelies powder coated red. And one set of Silverado steelies re-centered to zero backspace.
I also have a set of 2" wheel spacers sitting on the shelf.
For some reason I've always liked the "clean" look of the Silverado 17" steelies on an NBS
So haters gonna hate. But I like 'em
I really want to run 17" wheels, it'll be an actual off roader so steel is not as blingy, but better for hammer trail fixes of bent beads.
So at the moment I'm not super open to "hey man you should run FUEL __________s....." Or something. But who knows that could change.
The 16" are these black steelies (I was measuring upward travel with the torsion keys pulled in this pic)
The red stock Silverado steelies are from a previous truck. I'm not sure I like the look on this one. But on the desert tan truck i had them on, with 35s they looked sick
Here are the re-centered ones. This pic is right after welding, before the slightly rough lip around the edge was cleaned up on a lathe. And before powder coat. They're at the powder-coaters right now going stock silver.
So for this build, which is sort of an "overland traveler" build.
I really want a tall-ish but narrow tire. Ideally
33"-34" tall, 10.50" wide. Most if not all tires measure an inch shorter than indicated size.
So the tire i want would be a 35x10.50R17.
Basically a non-existent tire.
Off Road race only tires meant for light buggies come in 35x10.50-15 but i don't even know if 15s would clear. And race only tires don't last long (that's what i had on those red wheels actually). Not to mention 15" wheels basically say "hey, I'm stuck in 1994. . ."
The plan is to test fit a buddy's 285/70r17s once it's under its own weight, and see how those look. If that size looks good, we'll go that way. If it looks like it skipped leg day, then we go bigger.
But 35x12.50 i think will lose the "overlander" look, and venture closer into "every other Chevy with a lift on the road" look.
The current build at estimated right height, would put the edge of fender lip at 41" up from the ground with 285/70r17s.
Opinions? But that might not look too bad tire size wise?
How about a 295/70/17 or 305/70/17? Both get you a little more height than the 285 but still less than 12.5 wide.
curious to see what those recentered wheels look like after powder. K2 generation steel wheels would be another option if you wanted a little more width.
I think a 285/70r17 would look to small. Kenda klever r/t comes in a 35x10.5r17 and you can get a nitto trail grappler in 35x11.5r17. Im also curoius to see how those wheels look when they're done and on the truck.
Good call, KENDA and NITTO have some appealing sizes
BFG also has a 34x10.50R17 but only in the KO2, which i love that tire. I've gone through a set on this rig already. But i was hoping for maybe a mud terrain this time around. But that could change.
As for INTERCO, they seem to be the only company consistently offering narrower tires versus height over the years. But I've not had good luck with INTERCO on anything that goes long distances- hard, rough, shaky, loud.
The wife's comfort is enough of a factor, so I'm trying to keep as much of the refinement. As i can.
That's also why I'm keeping ABS, not because i love the feeling of a pulsing pedal in low traction situations. But rather so that I can keep the Auto 4wd t-case. And I know that's another one where haters are gonna hate. But she likes it.
I don't have any with them in yet. I am waiting for my wheels to come back from blasting. And taking the lowering kit out so "on" is not accurate. But I have the at-r.
I didn't post before the reason that the Steinjaeger track bar will fit even better.
Here's the diff cover that it's getting. The square shape of the cover lends itself to the shape of the steinjaeger bar nicely.
With all the measurements I've taken, it looked like to get what i wanted, and with how the dodge parts worked out. I needed 1-1/2" lift in the front and 3-5/8" in the rear.
There's not really any 1.5" lift springs for the dodge available. But 1.5" spacers were easy enough.
And Rough Country had rear springs that will net me 3.75", which is close enough.
At some point in the future i might address the fact that their springs are grey not red. But it seems insignificant at the moment.
The Rear springs compared to stock
Now that I've installed the rear springs, I was able to measure for rear shocks. Next I'll get ProComp rear shocks that match the fronts.
Ha ha, even by the end of this post it's starting to bug me that the springs are not red lol.
*edit
Once the dust settles on the front swap, and i get whatever tires i end up with.
If and when I have enough money, I'll build long arms and a track bar for the rear. The rough country kit these springs came from uses stock arms. So I know my stock rear arms won't be catastrophic in the meantime.
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