THIS IS THE PLACE TO LIST AND SELL YOUR TRUCKS AND PARTS FREE!

Home of all dually trucks with the GMC/Chevy 3500HD series truck a point of interest.

By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please register for an account above!

You can appreciate the “beef” of the GMC/Chevy 3500HD trucks, a stripped rolling 3500HD chassis weighs more than a running C1500!

When posting on this site you won't have to explain what the 3500HD Beast is! ie 19.5 wheels, straight axle, 10 bolt wheels, 15000lbs GVW, 4 Wheel Disc Brakes etc

We are based in the U.S. If you are not from the U.S. or Canada (all IP addresses checked) you will be rejected. If you are a legit overseas applicant, contact me via email: borderdrop@yahoo.com


Welcome to the 3500HD.com forum created October 2009

Author Topic: Spring-Over 4x4 conversion to Spring-Under.  (Read 8106 times)

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Spring-Over 4x4 conversion to Spring-Under.
« on: January 02, 2011, 06:58:17 PM »
Well I'm tired of lifting 5' to put things in the bed of the truck, and jumping in and out, so I'm in the process of lowering my 4x4 3500HD 4" by removing the rear lift block, and doing a Spring-Under conversion.

The rear is/ was easy, I simply had to remove the 4" lift block, and install new U-Bolts. This step took about 15 minutes  ;D

Before



After




And then I've been working on the front axle. I have a Dodge Dana 60, and it's much more narrow than the Dana 70 that was fitted into these trucks. So, in order to mount a spring perch on the under side of the axle, I had to move the differential towards the center. This is because the 60 originally had one U-Bolt on the differential, and two studs cast in the housing to hold the other half of the U-Bolt plate. I added 2.71" to the short side of the axle, and after making up the difference in spring pad widths, I'm able to move the spring pad center away from the differential 1.625". I used 2.125"x .120 wall DOM to sleeve the three pieces back together, and a piece of 3.125"x .500" wall DOM to match the original axle tube. The 2.71" is the exact measurement a Ford Dana 60 axle shaft was longer than my original Dodge shaft.





More to come tomorrow after I spend some more time out in the shop.
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #1 on: January 04, 2011, 05:25:29 PM »
And on to the front!  ;D

After welding in a new crossmember towards the front, I removed a large portion of the factory engine crossmember to resemble that of a factory K3500. Then I removed the old axle and all associated parts to make way for the new Spring-Under axle I had made. After playing with mounting options and height, I worked out a way to install the axle with the leaf spring in the factory position. This gave me a near stock height, and I couldn't be happier!!!

Again, here are some before and after shots.



Keep in mind, that those are 8R-19.5" tires, and measure 33" tall.

Here's a shot of how the drivers side sits.


There is still some work to do, I have a couple loose ends that need attention, and I have to make a new Panhard bar. But overall, I've had fun and it hasn't been too challenging of a job.
« Last Edit: January 04, 2011, 05:28:03 PM by Raymo »
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #2 on: February 23, 2011, 12:06:27 PM »
Alright, after revamping the steering, and building new trac bar mounts, I've gotten a few miles on the new setup.

It feels as solid as can be, and is much more useable and user friendly.

It measures 26" to the top of the front bumper, and 40" to the top of the wheel well (which is 4" taller than my father in law's C3500)

So overall, I dropped the 4" in the rear, and an amazing 7" from the front.

« Last Edit: February 23, 2011, 12:08:16 PM by Raymo »
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

someotherguy

  • 3500HD Hero
  • *****
  • Posts: 882
  • Age: 47
  • Location: Texas
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #3 on: February 23, 2011, 03:16:05 PM »
Raymo!  Looking great!  I will be perfectly honest and tell you that in the recent past I was looking at the truck and thinking to myself, man, it looks...kinda akward!

Now it looks like it's supposed to.  Hard to believe you've got 4WD under there now.  How much travel do you think you've got in there before (what) hits (what)?

As far as the width of the rear using the standard longbed, were the aftermarket flares required to get the width you needed for coverage, or do you think factory 4WD rear flares would have worked?  (They match the front flares)

I'd like to build a truck like this myself, except out of a 159.9" truck so I can build an extended cab - but not shortening the frame; keeping the wheelbase correct and grafting onto the front of the bed to lengthen it that miserable 4" difference. :D  The Cummins in yours is a great swap, but I'd be sorely tempted to continue running a big block, just because I'm not a diesel guy.  Maybe if I had a Cummins laying around, I could be converted, so to speak. :D

The cool part is I could still run a Sneeker wheel lift wrecker unit under the bed, attached to the frame, and it would be a totally functional self-loader wrecker.  The tough decision would be whether to mount the Sneeker between the frame rails, as was intended, or up on top of them inside that framework that Nick (MrBeast) built.  The cool thing about the framework is that not only does it make the unit quickly removable if need be (proven), it also positions it higher so that it ends up with more usable lift.  The lower to the ground it is, the lift ability just becomes "self-lifting" which is handy for changing your own back tires, but not much else...  Problem is, if I use the framework in addition to a pickup bed, I'll have to do some hard thinking about how it's all going to fit, as I'm sure the framework is taller than the gap you need to close up to put a pickup bed on an HD frame.

Again, congrats, nice work - the truck is looking really sharp now.

Richard
« Last Edit: February 23, 2011, 03:19:53 PM by someotherguy »
06 Silverado ISS / 06 Silverado SS / 06 300C SRT8

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #4 on: February 23, 2011, 05:20:45 PM »
Thanks!

And trust me, no one thought it looked worse than me haha, it drove me up the wall looking out at the driveway and seeing that elephant sittin' there  ;D Don't get me wrong, I've built my fair share of off road OBS', but it was just all wrong for this one.

As for travel, I managed to cut back enough to get 3" upwards before it hits the trac bar. I'm taking it easy until I get my bumpstops installed, but luckily after a few hard potholes I still haven't stuffed anything.

I did however narrow my Cummins pan by 2" on the differential side, but really just for piece of mind. I did do some measuring and a BBC pan would fit just fine.

For flares, I have 5" extended coverage Bushwackers, they're pocket style, which I don't like because of the smooth fronts. So when I lay some good color in the spring I'm going to fill the pockets and smooth it all out. The factory flares only give 1" of added coverage, but the 5" covers perfect.

As for running a sneaker, I used Poly cab mounts that meant I had 3" to fill between the bed and frame. So that's about half of what was used in the sneaker build? Maybe after removing the factory bed supports, or even notching each one it would lay down good. I can't remember how tall they are but I'm willing to bet it would come close with the framework you have.

And thanks again, next step is a nice interior, and a nicer paint color, have it narrowed down to two color choices, but I have a couple months to figure that out.
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

merlin5577

  • Global Moderator
  • Dually Driver
  • *****
  • Posts: 181
  • Age: 32
  • Location: Taunton, MA
    • Great site for all trucks!
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #5 on: February 23, 2011, 07:27:36 PM »
Awesome job! And awesome write up!  ;)
-Robert.
My Trucks;
2003 Chevrolet Silverado K2500HD 4X4 6.6L w/Allison 1000
1997 GMC Suburban K1500 4X4 5.7L w/4L60-E
"If you dont stand behind our troops, feel free to stand in front of them."

Benito

  • Single Axle Driver
  • *
  • Posts: 7
  • Age: 35
  • Location: VT
ABS
« Reply #6 on: July 05, 2011, 05:46:44 PM »
Thanks for the very helpful write-up. Did your truck have abs front and rear, or RWAL? I'm planning ahead and hoping to do a spring under D60 or 80/60 hybrid this winter & would like to keep abs or possibly convert to RWAL?
I know there are tone ring kits for SAS on newer Chevys, does anyone know if the tone rings are the same on our trucks?
2000 3500hd 6.5 nv4500 28k miles pto dump
2006 2500 ccsb D/A 130k
2001 kubota kx161-2

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #7 on: July 05, 2011, 06:53:50 PM »
My truck, being a '94 had RWAL but due to the nature of the build of the truck itself, it's no longer there  ;D

And as far as the retrofit tone rings, I'd try to get a tooth count and a diameter of what you're trying to match and call the manufacturer, or see if theres that info already floating around.

I know exactly what kit you're talking about but having a hell of a time remembering the name!

Oh, and I had studied the 60/80 axle, too since I've got a few of each... Sick minds think alike  8)
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #8 on: July 05, 2011, 06:57:09 PM »
Also, if you have any questions or want a specific picture, post up and I'll get/answer whatever you want. I might still have all my renderings and measurements that I had taken before hand.
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

Rayjon237

  • Dually Driver
  • ***
  • Posts: 142
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #9 on: December 07, 2011, 09:50:54 PM »
you mentioned cummins,  I have a cummins in my 3500hd also,  can you take a pix of where you modified the oil pan and how close the diff is to it??   I lowered the cummins in mine some for better clearance arround the belhousing and for the fan..  would like to do a 4x4 conversion at some point and am gathering info..  Thanks Ray, 

BTW really like how it looks with the spring under...

Raymo

  • Global Moderator
  • 3500HD Driver
  • *****
  • Posts: 381
  • Age: 30
  • Location: Port Huron Area, MI
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #10 on: December 09, 2011, 01:23:25 PM »
I'll try to get you a picture sometime soon, just got some fresh snow so it might be a little bit  :D

I basically cut a 2" section from the passenger side of the drain plug the length of the sump, moved the curve over to keep the profile of the pan, and filled the space that runs parallel to the pan rail. Gives JUST enough room to slide the pan up around the giant pickup tube.

It was more for peace of mind, as I could have hit the track bar before the pan. But if something ever happened I didn't want to lose the engine as well.

Having done it with a Dodge Dana 60, the next time I do it I'll be using a '78-'79 F*rd housing. It's set up on the differential side to accept this mod much better than the GM-Dodge housing, and with a quarter of the work.
'94 3500-HD, Cummins, Getrag, NP205. Shortend rear frame with a Pickup Bed. Dana 60 front, stock 80 rear.

'03 2500-HD 8.1 and Allison

malibu795

  • Single Axle Driver
  • *
  • Posts: 49
Re: Spring-Over 4x4 conversion to Spring-Under.
« Reply #11 on: February 23, 2012, 06:02:19 PM »
got any pictures of the crossmemer?

 


LINK SECTION - FEEL FREE TO SUGGEST ANY LINKS (YOURS INCLUDED).




DIESEL HUB

DIESEL PLACE

VINTAGE CHEVY/GM FORUM