Solid Axle Swap into a 1998 Astro AWD

jakepatch · Post by **jakepatch** » Tue Sep 12, 2006 4:54 pm

Dean, sent you an email, please respond.. Thanks

jakepatch · Post by **jakepatch** » Thu Sep 28, 2006 6:59 pm

Dean, while comparing your swap with one that is on the pirate4x4 site, I noticed on the front axle they have the shackles at the front of the springs, and you have the shackles at the rear of the springs, can you explain the reason for this? Getting ready to start figuring out my brackets and deciding which way to go. Thanks.

LiftedAWDAstro · Post by **LiftedAWDAstro** » Fri Sep 29, 2006 3:35 am

The reason for having the shackles at the rear is that when the leafs compress the rear of the leaf moves backwards. Of course this is only true if the leaf has some arch to it. For a wheeling rig, the shackle at the front won't really hurt performance. But for on-road performance, the ride will be better when hitting bumps and pot holes in the road. Think of the front section of the leaf spring from the mount to the axle as a solid swingarm that will move up and down with suspension travel. The arc will move the axle rearward a little bit.

jakepatch · Post by **jakepatch** » Fri Sep 29, 2006 5:07 pm

So I'm thinking I might want to do the shackles up front then.

lockdoc · Post by **lockdoc** » Fri Sep 29, 2006 6:54 pm

Sounds like Dean is saying if you are going to use your rig for a daily driver and off road you will want the shackles at the rear for a better highway ride. Clarify Dean as I can't tell from your post.

jakepatch · Post by **jakepatch** » Fri Sep 29, 2006 7:16 pm

I will be using my van for both on and off road, probably more on than off, so I was understanding for a better ride on road shackles up front, right Dean??

mdmead · Post by **mdmead** » Fri Sep 29, 2006 8:01 pm

Better ride equals shackles at the rear.

With shackles at the front, a bump hit, pushes the axle forward, causing a bigger "jar". If the shackle is at the back, the axle can move rearward a bit, further smoothing the bump.

At least that's the theory.

I recently read where the shackle at the front might be preferred off-road as Dean indicated. It sounded like the reasoning was that by pushing the axle slightly forward when hitting the bump would increase traction and help pull the tire up and over an obstacle. I think it was mainly talking about playing on the rocks.

I know my Super Duty has the shackles on the rear of the springs on it. But it still rides like s&@t!

mdmead · Post by **mdmead** » Fri Sep 29, 2006 8:04 pm

Dean, I was looking at your shackle mounts in the pics here and I'm just wondering if you added any more bracing to them than shows in the pic. While the steel you used looks pretty beefy, it also looks like it is a solid bar and could bend up with a big enough hit. I know your engineering is always pretty beefy though.

LiftedAWDAstro · Post by **LiftedAWDAstro** » Sat Sep 30, 2006 7:22 am

What the heck did I write? LOL

To clarify...just listen to Matt. He is right on the $$ with the shackles in the rear.

Oh and Matt...those pics are not of the finished product. They are fully welded and braced on 2 sides at an upwards angle. It isn't the best design, but it is VERY beefy!

My next design will have the fron converted to a 3 or 4 link with either coils and shocks or coilovers ($$). I think for about $1k the front can be slung with coils, shocks and a link type suspension. I am very seriously considering getting an AWD subframe, another D44 solid axle and doing the conversion. Then I would sell the subframe with axle, but I would make templates or drawings of all the brackets so I could do more swaps. I know there could be a few sold that way but I don't know if the time to fabricate would pay off in the end.

mdmead · Post by **mdmead** » Sat Sep 30, 2006 12:01 pm

LiftedAWDAstro wrote:What the heck did I write? LOL

I understood you the first time!

jakepatch · Post by **jakepatch** » Sat Sep 30, 2006 7:23 pm

Ok, so shackles at the rear it is! When I get a little along I'll start up a new thread and quit hijacking yours!

9dawgs · Post by **9dawgs** » Wed Oct 18, 2006 11:05 am

Very nice... Okay so what about us poor saps who have the RWD version Astros and want to upgrade to 4x4? Can you place a solid axle in these rigs without too much difficulty? I know the frame would have to be modified to fit the transfer case but how much trouble would it be? Maybe I should just look for an old '98/'99 AWD... :-k

LiftedAWDAstro · Post by **LiftedAWDAstro** » Wed Oct 18, 2006 4:51 pm

To fit a solid axle into a 2WD subframe will require a new tranny crossmember to accomodate the 4x4 tranny and t-case as well as modifying the crossmember under the engine. Your best bet would be to find an AWD subframe to use. If you have the fab skills and shop space the mods need to a 2Wd subframe would be fairly easy to do.

BLAZER · Post by **BLAZER** » Wed Oct 18, 2006 5:50 pm

My 87 K5 blazer had the shackles in the rear from factory and all the K- 4x4 trucks were like that. I would recommend that you put shackles in the rear.
Dean, hurry up with that new design so I can buy your old stuff from ya

$\:D/$

9dawgs · Post by **9dawgs** » Fri Jun 08, 2007 6:11 am

Ok, looking at this post again just makes me want to go out and buy an AWD... I've got to stay away from this post! One day, one day...

Dean, your fabrication skills are awesome. Do you teach classes?? $\:D/$

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Solid Axle Swap into a 1998 Astro AWD