Converting 6 to 8 lug (AXLES)

[AvaAvalanche]

Can anyone point me in the right direction to find all the info needed to swap my ‘06 Ava 1500 z71 from 6 lug hubs/axle to 8 lug. Ideally, I would like to use 2500 axles on my 1500 z71 but if it is not cost affective then if I can do just hubs I would be satisfied. I know someone is going to say just buy a 2500 and that’s not what I want to do. I am quite attached to this truck and want to make the conversion. Also, I get the legal GVWR so I am not interested in hearing about that either. Thanks in advance!

Cheers,

John

 

[ygmn]

you will have to just do it and report back as no one I can remember ever posted a HOW TO axle swap from1500 to 2500 axles.

WHY?

Lots of work involved welding bracket making etc since 2500 leaf sprigs in rear and 1500 has 5 link suspension.

Just buy a 2500 and have 2 trucks is probably cheaper route.

 

[Randy]

I believe for the rear you can swap a Hummer rear end which is 8 lug and a pretty much a bolt except for the shock mounts, not 100% sure but it's been done here... The front on a 1500 HD has 8 lug, I don't know if anyone here has completed one, if somebody has, please jump in here...

 

[redheadedrod]

The best way to do this in the rear is to buy an H2 rear end and slap it into your truck. Will bolt right in. The only issue is that it's likely a 4.10 gear and your truck likely has a 3.73 gear. My truck loved the H2 rear end in it. Be aware it will lift the rear 1-2 inches and you will need a shorter driveshaft by 1.25" and at a minimum need a new U-Joint that can mate up to both the 1500 driveshaft and the H2 rear, but when you shorten the drive shaft it is easier to just have the compatible end welded on. There is a thread on here that goes over it. I found that H2 rears were about $350. Shipping costs almost as much as the rear will cost you so its best to pick it up.

Then put a 2" spacer/adapter on the front. They make them that go from 6-8 lug.

This is the ONLY way you can do it... And its dicey to put the spacer/adapter on the front. That thread mentions that it might be possible to use the upper and lower control arms off a 2500 or 3500 as they MIGHT bolt on at the frame. You may need to modify the outer Tie rods. I never got that far. I have a 2500 now.

The adapters you can get to do this are 2 piece and you can NOT put them in the back and try to tow with them. They WILL break. With these adapters you make that axle able to tow less than what the axle originally could do.

Also be aware that it will be very dangerous to tow weights beyond what your truck as a 1500 is rated to tow. Don't get caught overloaded as it will be a big fine, if you get into an accident and someone gets hurt, don't be surprised if you do jail time if you are over weight, a lot of time if someone is killed. And its what the truck was rated at, at time of build. Any modification to that has to be certified by whatever agency is authorized to do so, and when I inquired about it, I was told there was no agency willing to take on the liability of increasing its load rating no mater what you do to it.

People put 2" spacers on the rear of the 2500's because the rear axle is skinnier than the front. Those that do those only use Steel adapters but they are also 8 lug to 8 lug so they shouldn't lose much if any load rating. Aluminum spacers are dangerous if you do ANY towing period.

 

[redheadedrod]

I believe for the rear you can swap a Hummer rear end which is 8 lug and a pretty much a bolt except for the shock mounts, not 100% sure but it's been done here... The front on a 1500 HD has 8 lug, I don't know if anyone here has completed one, if somebody has, please jump in here...

Yes I did the H2 swap. The shocks will bolt up but they are under tension. The tension is well within the specs of the shock though. Ran them about 5k miles before my 1500 got totaled in a rear end accident. I still have the H2 variable rate springs and Bilstien 5100 shocks I used in storage in MI. The shock mounts are at an angle and to the outside a little but as I said, they bolt right up.

 

[Randy]

I know you did; I was the one who told you about the H2 fitting the AV. As for the shocks, can't you buy the longer ones for a lifted vehicle??

 

[redheadedrod]

I know you did; I was the one who told you about the H2 fitting the AV. As for the shocks, can't you buy the longer ones for a lifted vehicle??

Yea was just adding to what you said. The Bilstien 5100's I bought said they were good from 0 to 3" lift.

 

[Randy]

Were they just that way when the wheels were off the ground, with the suspension extended??