Converting 99 astro to 6 lugs...

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madslammer
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Converting 99 astro to 6 lugs...

Post by madslammer »

Hi, I'm looking at some oem wheels I like, but they are 6 lug...
How complicated would it be to convert from 5 to 6 lugs...

I have drop spindles, so I think that would be an issue...???...

thanks...
'97 Astro 2wd, lowered 4" w/Belltech spindles and drop leafs.
'87 Astro 2wd, lifted, pretty close to 4" all around.

Kidhauler
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Re: Converting 99 astro to 6 lugs...

Post by Kidhauler »

The fronts you would just need to order new disks with 6 studs from a newer year. For the rears I think you would need whole new axle shafts with a 6 bolt flange. You would also need to order new drums with 6 holes.

I would look at different rims if you look at the budget of swapping all the parts plus the rims you could probably get some nice aftermarket rims.

I feel your pain I have seen several 6 bolt rims I liked at great deals that will not fit my 99
1999 Safari Touring edition.
trailer tow pack with a 3:73 posi
Bucket bench seats, Rear heat, Rear Airconditioning.
teal green
300 000 kms
AirRide air bags in the rear to fix soft stock suspension.
Onboard aircompressor to make it all work nice.
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madslammer
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Re: Converting 99 astro to 6 lugs...

Post by madslammer »

Thanks...
'97 Astro 2wd, lowered 4" w/Belltech spindles and drop leafs.
'87 Astro 2wd, lifted, pretty close to 4" all around.

LiftedAWDAstro
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Re: Converting 99 astro to 6 lugs...

Post by LiftedAWDAstro »

Kidhauler wrote:The fronts you would just need to order new disks with 6 studs from a newer year. For the rears I think you would need whole new axle shafts with a 6 bolt flange. You would also need to order new drums with 6 holes.
None of this will work. The fronts are unit bearing and take standard rotors like the AWD's. The rears are rotors as well and while this swap, in theory could be done pretty easily by using the 5 lug axle shafts and re-drilling the rotors to 5 lug, I bet the time and effort are not worth it when when you can get aftermarket wheels fairly cheap.
Current rides:
2013 Toyota Tundra DC 4x4
2008 Dodge Nitro 4x4
2005 Nissan Sentra 1.8S Special Edition

Mileage spreadsheet

Vans owned:
1986 Safari 2.5L 4 speed manual - scrapped
1995 Astro 2WD conversion 4.11 posi, shift kit, DHC rock rails - sold to Skippy
1998 Astro 4x4 D44, D60, NP231, full hydraulic system with 9k# Milemarker winch and snow plow - sold to Lockdoc
2003 Astro AWD all stock - traded for a 3/4 ton truck
2005 AWD, 4.10's - sold to skippy
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Re: Converting 99 astro to 6 lugs...

Post by doyoulikeithere »

LiftedAWDAstro wrote:
Kidhauler wrote:The fronts you would just need to order new disks with 6 studs from a newer year. For the rears I think you would need whole new axle shafts with a 6 bolt flange. You would also need to order new drums with 6 holes.
None of this will work. The fronts are unit bearing and take standard rotors like the AWD's. The rears are rotors as well and while this swap, in theory could be done pretty easily by using the 5 lug axle shafts and re-drilling the rotors to 5 lug, I bet the time and effort are not worth it when when you can get aftermarket wheels fairly cheap.
So, how could you convert the front to 6 bolt from 5? I've wondered about this everytime I consider getting a nice nearly new rear axle with LS and disk brakes...
Would be sweet if it was as easy as buying 6 bolt unit bearing rotors !!
2021 Yamaha Tenere 700 - Blue.
2016 Yamaha XSR900 - Silver.
1990 Astro - AWD - Brown.
1987 Astro - With 5 Speed & 4wd - Silver & Blue.
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madslammer
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Re: Converting 99 astro to 6 lugs...

Post by madslammer »

Well, I know there are some fine wheels that fit the 5 lug pattern, but I was trying to get a set of SS or Denali 20" OEM... Because the factory chrome is so much tougher than the aftermarket ones... Thanks, I guess I'll have to try the wheel Adapters and do some math with the Backspacin/Offset...
Thanks again guys...
'97 Astro 2wd, lowered 4" w/Belltech spindles and drop leafs.
'87 Astro 2wd, lifted, pretty close to 4" all around.

Kidhauler
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Re: Converting 99 astro to 6 lugs...

Post by Kidhauler »

On a 2wd the studs are in the disk so it should be as simple as ordering disks off a 2000 and putting them on your spindles.

I think dean was thinking of AWD front ends. The aftermarket disks I put on my van were $150 a peice retail plus bearings.
1999 Safari Touring edition.
trailer tow pack with a 3:73 posi
Bucket bench seats, Rear heat, Rear Airconditioning.
teal green
300 000 kms
AirRide air bags in the rear to fix soft stock suspension.
Onboard aircompressor to make it all work nice.

LiftedAWDAstro
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Re: Converting 99 astro to 6 lugs...

Post by LiftedAWDAstro »

Nope, I am talking about the 2003 - 2005 2WD vans...they do not use the hub/rotor assembly like the 85 - 2002 2WD vans.

2003 2WD front rotors

2003 2WD front hub unit bearings

1999 2WD front hub/rotors
Current rides:
2013 Toyota Tundra DC 4x4
2008 Dodge Nitro 4x4
2005 Nissan Sentra 1.8S Special Edition

Mileage spreadsheet

Vans owned:
1986 Safari 2.5L 4 speed manual - scrapped
1995 Astro 2WD conversion 4.11 posi, shift kit, DHC rock rails - sold to Skippy
1998 Astro 4x4 D44, D60, NP231, full hydraulic system with 9k# Milemarker winch and snow plow - sold to Lockdoc
2003 Astro AWD all stock - traded for a 3/4 ton truck
2005 AWD, 4.10's - sold to skippy
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Re: Converting 99 astro to 6 lugs...

Post by doyoulikeithere »

Kidhauler wrote:On a 2wd the studs are in the disk so it should be as simple as ordering disks off a 2000 and putting them on your spindles.
I think dean was thinking of AWD front ends. The aftermarket disks I put on my van were $150 a peice retail plus bearings.
So Kidhauler, Are you saying that you found an aftermarket disk that bolts onto a Gen 1 spindle, but has 6 lugs?
That would be a nice thing to find !!
Where are they and how much? oh ya 150...
Would go nice with a 6 bolt disk rear axle swap..
I wonder if any GM Truck 6 bolt front disks are the same style & possibly interchange with the 5 bolt astro disk ?
2021 Yamaha Tenere 700 - Blue.
2016 Yamaha XSR900 - Silver.
1990 Astro - AWD - Brown.
1987 Astro - With 5 Speed & 4wd - Silver & Blue.

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Re: Converting 99 astro to 6 lugs...

Post by Kidhauler »

No I thought they kept the same design just with 6 studs. The disks I put on are vented and slotted to handle heat better. It is very easy to warp the rotors when towing in the mountains.

So far I have done several trips with the trailer (4500lbs) and had no issues even when the temp was over 100f.
1999 Safari Touring edition.
trailer tow pack with a 3:73 posi
Bucket bench seats, Rear heat, Rear Airconditioning.
teal green
300 000 kms
AirRide air bags in the rear to fix soft stock suspension.
Onboard aircompressor to make it all work nice.

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Re: Converting 99 astro to 6 lugs...

Post by Bret Schmerker »

Concerning the 6-on-5-1/2" spindles, would I have to backport the 2003-05 steering knuckles to my 1997 SLE to use them? Whereas my current set-up uses Passenger (viz., Caprice/Roadmaster) spindles, 2003-up saw C/K-1500 spindles forward. Of course, the larger lug pattern would better accommodate a full-float axle such as my 9" Currie contingency (Currie Enterprises offers optional exact-contemporary Ford Explorer rear rotors for four-wheel discs, with the mechanical drums off the stock parking brake cables).
1997 GMC M11006 (Safari SLE, 2WD, V6-4300/4L60-E/7.625" 3.73:1 open)
Acquired Jul 2018 / In service Sep 2018 - Nov 2022 / down due leaky valve(s) #5 cyl.
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Stroverlander
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Re: Converting 99 astro to 6 lugs...

Post by Stroverlander »

Yes, probably. The '03-05 knuckles are different.

Is you van RWD or AWD?
2004 Astro LT AWD Stroverlander
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