Sprinter 4WD Conversion Idea, GMT-800 IFS.

luthj · Jun 11, 2019

Len.Barron said:
There are a bunch of 4x4 fab shops that sell taper adapters, I'm sure you can find one that has what you need..

Its possible, I have a few emails out for details. Most I can find are 1.5/12 too 2/12 taper conversion.

b dkw1 · Jun 11, 2019

Aluminum tube spacers is a bad idea. Spacers in general are a bad idea.

Len.Barron · Jun 11, 2019

luthj said:
Its possible, I have a few emails out for details. Most I can find are 1.5/12 too 2/12 taper conversion.

I'd make that your backup plan, any solution that puts a bigger joint in there would be at the top of the list.

luthj · Jun 13, 2019

I ordered a 2013+ 2500 UCA. Here is some comparison shots. The good news is that it uses the same BJ shaft as the early 2500.

IMG_20190613_171109866 by J Luth, on Flickr

IMG_20190613_174615564 by J Luth, on Flickr

IMG_20190613_171136560 by J Luth, on Flickr

Its got a bit shorter pivot to BJ length, and the bushings are a bit narrower. However the bushings are much beefier. I think I can adjust the press depth if needed. As the rear bushing as is would be very close to the spring.

Total BJ angle is around 50 degrees. But its biased mostly towards droop. That does restrict how low I can mount the bushings, and still get close to symmetric travel. Yes, I know my garage is a mess. I have a herniated disk, so i can't lift ******** for another week or two.

IMG_20190613_182222647 by J Luth, on Flickr

IMG_20190613_182422449 by J Luth, on Flickr

The BJ on this unit limits travel to about 7.75" before the BJ binds. I think I can improve that with some light grinding on the casting though.

Now for clearance. Bump is no problem. Droop has some grinding to do. There is a bit more outside edge thickness than the model shows. I think I can clearance grind the arm, and weld a piece of rod to the upper outside to restore any strength reduction. Its about 50% thicker than the 1500 UCA to start with.

luthj · Jun 13, 2019

Here is my spacer/shim idea. The 1500 taper is only .08" off from the larger 2500 BJ. So I grabbed some .045x1/2" aluminum tube. Cut two sections from it, and bent them into partial cone shapes. I torqued down the stud, and it formed them into perfect spacers. It took a few good taps to get the BJ free, which is a good sign. If I like the design, I can make some from steel tube stock. They are re-usable.

Of course this presents an interesting conundrum. The 1500 UCAs are cheaper, and require no modification. However they are lighter duty, though the bushings are about the same as the older 2500 style. The late style 2500 UCA has a slightly larger BJ, and bigger bushings. However, it needs modification to fit. With the BJ being non-replaceable, that means making the modifications every time I need to change the BJ. Given that changing UCAs is not terribly difficult, and the parts are fairly compact, I am leaning towards the 1500 UCA with shim/spacer. I can carry spares if needed, and I can get them in most any american auto parts store same day.

IMG_20190613_203959075 by J Luth, on Flickr

IMG_20190613_203945604 by J Luth, on Flickr

IMG_20190613_203821323 by J Luth, on Flickr

b dkw1 · Jun 13, 2019

Those split shims will spit out. There is nothing to keep them in place. Maybe if they were one piece, but shims are still a bad idea.

Len.Barron · Jun 13, 2019

Teraflex makes a few of these https://www.amazon.com/Teraflex-990...ert/dp/B00S1AWE50?ref_=bl_dp_s_web_8488513011 and may have the one you need, just bore the hole in the knuckle up and tap them in. Ruff Stuff makes a couple different ones as well https://www.ruffstuffspecialties.com/catalog/INSSTEER-2PK.html
I've actually welded up tie rod holes that were blown out and redrilled and tapered them so you could do that as well

Pinnacle Campers · Jun 13, 2019

How about something like these with a replacable bolt in ball joint?

Loading Products... | Speedway Motors, The Racing and Rodding Specialists

www.speedwaymotors.com

luthj · Jun 14, 2019

b dkw1 said:
Those split shims will spit out. There is nothing to keep them in place. Maybe if they were one piece, but shims are still a bad idea.

I did a quick loading diagram, and I don't see them coming loose as long as the bolts tight. They can't migrate down due to the nut. Upwards might be possible. Regardless, my plan is to make a pair from steel tubing, and I can just tack weld them into the bore, or even to the BJ if needed. Obviously its not ideal, but that taper is under immense pressure once torqued down. If needed, I can do a inspection every 1000 miles. The worst case failure is a worn bore, no real safety issues I can see.

Len.Barron said:
Teraflex makes a few of these https://www.amazon.com/Teraflex-990...ert/dp/B00S1AWE50?ref_=bl_dp_s_web_8488513011 and may have the one you need, just bore the hole in the knuckle up and tap them in. Ruff Stuff makes a couple different ones as well https://www.ruffstuffspecialties.com/catalog/INSSTEER-2PK.html
I've actually welded up tie rod holes that were blown out and redrilled and tapered them so you could do that as well

That looks promising. I will order a couple to see if any are the right size. Best I can tell, most of those steering BJ tapers are 1.5:12. I need 2:12, which makes this a bit of a challenge.

brian94ht said:
How about something like these with a replacable bolt in ball joint?

Loading Products... | Speedway Motors, The Racing and Rodding Specialists

www.speedwaymotors.com

I have been toying with making a set of custom UCAs using bolt in BJs, It would be a single piece of laser cut 1/2" plate. I am trying to avoid machine work, as that adds time and cost. So attaching the bushings is the challenge. I want to stick with factory style bushings for NVH and longevity. I have had bad experiences with urethane units in the past.

Len.Barron · Jun 14, 2019

Rough Country Silverado 1500 Forged Upper Control Arms for 2.5-3.5 or 7 in. Lift 19401A (07-16 Silverado 1500 w/ Stock Cast Aluminum or Stock Cast Steel Control Arms)

FREE SHIPPING! Offers Better Handling and Wheel Articulation. Enhance your Silverado 1500’s off-roading capabilities by switching its stock upper control arms w

www.americantrucks.com

something else to look at..

luthj · Jun 14, 2019

Len.Barron said:
Rough Country Silverado 1500 Forged Upper Control Arms for 2.5-3.5 or 7 in. Lift 19401A (07-16 Silverado 1500 w/ Stock Cast Aluminum or Stock Cast Steel Control Arms)

FREE SHIPPING! Offers Better Handling and Wheel Articulation. Enhance your Silverado 1500’s off-roading capabilities by switching its stock upper control arms w

www.americantrucks.com

something else to look at..

The issue I am running into with the lift kit UCAs, is they have extra BJ angle. This means I need to raise the mount higher to avoid binding on bump. Which translates to more downward angle on the arm in droop. More angle means less clearance for the spring. The aftermarket units are also a bit longer to allow for proper camber adjustment with a lift. Longer is not better for me either. The factory 1500UCA just barely clears the spring, I doubt the aftermarket units would clear with the pivot raised 2"? Though maybe the BJ on those units have better articulation.

Obviously custom is the best option design wise, but I am on a budget and a timeline. Hmmmm.

Len.Barron · Jun 14, 2019

Typically the extra length is offset by the extra angle producing the same amount of clearance(horizontal distance from mount to BJ center), you would have to increase the height of the mounts though, not sure if that is an issue or not(adding a second set of mount holes up higher would allow you to shift it down if you ever pursued a lift). I'm sure there is a middle ground of running some extra static BJ angle and some extra mount height that could possibly work for you.

luthj · Jun 14, 2019

Mmmm parts. Here's a 242D from a 98 durango. uknown mileage, but sounds a lot healthier than the last one. This unit has a second strongest chain (short of the hummer version). 32 spline input/output, and dual bushing diff. All it needs is a 6 planet gear set, and its ready for action (plus new bearings and seals).

IMG_20190614_163025273 by J Luth, on Flickr