How to Lower a Duramax 4X4?

[Bentley]

Going racing...

All cleaned up in the driveway...

I have some pictures of it at Famoso with the shell on it but they are not on this computer...

Bentley

 

[SIKDMAX]

WTF? Thats stock up front just cranked down and belltechs? Jesus your truck looks low!

 

[SIKDMAX]

How my truck sits right now with stock TB height and the shackles....

Planning on pulling my overloads, 2" rear hangars and 2" spindles up front with crankdown

 

[maxedout310]

notch it and bagg it.

 

[Bentley]

WTF? Thats stock up front just cranked down and belltechs? Jesus your truck looks low!

The way the truck is sitting right now, it is lower than that. I took 10 turns out of it from leveled when I put the 20's back on were as I had 8 before. I think I could still get another inch or so out of the front before the bolts are completely out... Now I am just debating doing the 2" drop for the front hanger on the leaf springs or going to a 4-link/trailing arm style rear with some coil overs...

I really need some sway bars!! The truck would handle like a dream then!

Bentley

 

[SIKDMAX]

Yes, Federico bars are my next purchase - I just gotta figure out whats up with that rear link and MBRP 5" kits, etc etc. I REALLY want a set.

 

[duratothemax]

Yes, Federico bars are my next purchase - I just gotta figure out whats up with that rear link and MBRP 5" kits, etc etc. I REALLY want a set.

I have that kit and love it. Really nice when hauling lots of heavy stuff in the bed.

You will have to make your own rear links and mounts. I have mbrp 4" duals and had to make my own because the pipes were in the way of the included mounts. I just got some 1/4" cold rolled plate, cut out some tabs, drilled them, welded it all together, and then heated up the links with the torch to re-bend them.

 

[MAXLLY]

This is a tricky one for a 4 X drag truck.

The lower we go in the front the harder the angle becomes on the shafts, same as a lift kit only reversed. If you wanna get seriously low with 20's and run 4x at the drag strip you have to start softening the rear springs in an effort to get the shafts to level out under power.

IMO- (I am in the middle of it now). I think the way to do it is use a 2" drop spindle and crank the bars up until you get the shafts just below level and give it a try. The spindles will force you to use a 17" or larger rim, not all 17's will work but you have a better chance of them not hitting the lower control bolt.

If you wanna do away with 4x and save the 400 +/- lbs of transfer case etc... bring ALOT of tire to the rear end party. Get rid of the springs so you can tuck 18" wide tires with atleast 8" (16 total) of sidewall under the fender.

Good luck.

 

[Bentley]

What is strange about that is the geometry in the front of my truck sits about 10* negative. If I put 2 turns back the t-bars it would be perfectly level.

Bentley

 

[SIKDMAX]

Crap... just realized if I get low with spindles I wont be able to run the PYOs with Drag Radials or cheater slicks.... crap.....

 

[MAXLLY]

Crap... just realized if I get low with spindles I wont be able to run the PYOs with Drag Radials or cheater slicks.... crap.....

I didn't try stockers yet. They are 16's IIRC? I put H2's on it (w/ spindles) and if you trimmed the lower control nut it could be really close. IIRC the H2's are 17's? Bummer! Not many slicks for 17, 18 or 20. Try Hoosier as well for the strip.

It would be cool to try a 35-36" wrinkle wall that was 12-16" wide... rollout becomes a problem. Plenty of width and sidewall though.

Bogart Racing Wheels 8 lug under 12" $500 +/- over 14" wide $650 +/-.

 

[SIKDMAX]

Was planning on getting some M&H drag radials and running on the stock 16" PYOs.... not gonna work with those spindles though...

 

[MAXLLY]

Nope, not on stockers, not even close.

I asked Santa for a set of 15" rims that would fit over 16" brakes and I haven't heard a thing since x-mas.

The elves are worthless and overated.

Some guy with a Dodge switched over to 1/2 ton running gear.

 

[Diesel Pilot]

Aren't you guys riding on your bump stops up front with the TB's slammed?

I can get pretty low but with the bump stops, not as low as you guys are talking. Mine bottoms out and the half shafts are perfectly straight.

I lose about 2" with the rear springs clamped but it is way to rough to drive it on the street like that. I might look into 2" drop shackles, Jeg's has them for $50.

 

[MAXLLY]

I didn't check it when i had the motor in last. IIRC it looked ok, they could always be trimmed. Perhaps the rods have realized some fatigue and don't have the resistance they once did?

As for the back i have a 4 link with 4.5" of ride (frame to axle), we cut the bumps in half. I can adjust up or down to a point without throwing the IC into the sky.

 

[mick]

This is a tricky one for a 4 X drag truck.

The lower we go in the front the harder the angle becomes on the shafts, same as a lift kit only reversed. If you wanna get seriously low with 20's and run 4x at the drag strip you have to start softening the rear springs in an effort to get the shafts to level out under power.

IMO- (I am in the middle of it now). I think the way to do it is use a 2" drop spindle and crank the bars up until you get the shafts just below level and give it a try. The spindles will force you to use a 17" or larger rim, not all 17's will work but you have a better chance of them not hitting the lower control bolt.

If you wanna do away with 4x and save the 400 +/- lbs of transfer case etc... bring ALOT of tire to the rear end party. Get rid of the springs so you can tuck 18" wide tires with atleast 8" (16 total) of sidewall under the fender.

Good luck.

Using 2" Spindles and cranking the torsion bars up, or using stock spindles and cranking the torsion bars down is exactly the same thing. there is no difference. At the end of it all, your axle angle is going to end up where its going to end up at a given ride height. You can only drop it so far and thats all before your cvs will snap (like 2 sets of mine). Ive tried every possible combination to get mine low with 4x4 but eventually removed the front diff and axles. Depends what you call low too I guess. My lowest spot is the cahssis rails that are 3" off the ground. I have McGaughys 2" Spindles with 20" Rims.

 

[MAXLLY]

Understood Mick. In my truck, for whatever reason, I had alot to raise. I used the adjustment bar bolt as a reference for what direction to go. My truck will not sit as low as yours.

BTW- Mick did it long before i thought about it, provided me with a TON of info. Thank again Mick.

OT- Mick did you bind the front axles at launch or further down the track when the front end settled? In other words at 20 mph or 80 mph, under full throttle of course.

 

[mick]

Understood Mick. In my truck, for whatever reason, I had alot to raise. I used the adjustment bar bolt as a reference for what direction to go. My truck will not sit as low as yours.

BTW- Mick did it long before i thought about it, provided me with a TON of info. Thank again Mick.

OT- Mick did you bind the front axles at launch or further down the track when the front end settled? In other words at 20 mph or 80 mph, under full throttle of course.

First one snapped going out the driveway James. Even though I thought I had enough clearance, I didnt. So I went to 2x2. Then after putting SC on, I tried for more traction via 4x4 again and went through the excercise of putting diff, axles back in and being real careful about getting minimal axle angle (even though truck sat higher than I wanted) Then I went driving and all was ok until I done a fairly sharp corner at low speed and CRUNCH, sheared off one more. So out came axles and diff and back on its guts again where I like it

 

[MAX707]

Yes, I used the Bell Tech 6403's on mine as well. I put my stock shakles back in the rear when winter comes so I can mash around in the deep stuff but for summer there is no point to have it up that high. Also, my 20's would look silly with a leveled truck. I love the way it looks, rides and performs lowered. Gives it a little more of a street prowler look.

Bentley

I called beltech and they said the 6403's only fit up to 04'? Did you buy the old one's and they just mounted up?

 

[SIKDMAX]

6403s work fine from 01-08.