What size spacer

[Kaw-Liga]

Alright ya'll, I've got my stonecrusher TRO on the way to instal this weekend, and I know I'll be needing some wheel spacers to make it fit with my 76/77 disc brake knuckles, but how much should I get? I understand that I shouldn't use the 1/4" ones cause they are cheap-o- and will be dangerous, and I understand that if I go real big I'd be putting a little more load on my bearings and ball joints(although not any more than less BS wheels) Should I go ~1" to just achieve the clearance I need or should I go ~2" to both achieve the clearance I need plus increase my turning radius a little and get a slightly wider=more stable stance? I guess the question is mostly personal preference. My wheels are 15x10(BS I'm not positive but I think it is ~3.5") with 36x12.5 TSLs. Stock radius arms although I think I will do the weld on extensions from Stonecrusher sometime in the near future. Bring on the opinions as to what size I would be best with. Thanks for the knowledge!

Rob

 

[ctowery]

If you have 3.5"bs you should be fine? And who says 1/4" are crap. I used them for years! I also made some 1/8" spacers that worked. As long as you have enough lug nut-stud contact your fine IMO.

Cary

 

[Steve]

I use 1" spacers on mine. Got them from Spidertrax.

 

[Kaw-Liga]

I've just read that the smaller thickness "spacers" are prone to cracking/breaking whereas the thicker "adapters"(the ones that you bolt to the hub then use the studs on the adapter to mount the wheel) are much better quality and are the way to go. I guess there isn't that much difference in an inch, so maybe I'll get a 1 1/4" spacer as a comrpmoise. I don't want the tire to stick out too much and make it look stupid.

Rob

 

[Steve]

If you get the spacers (adapters, actually) that bolt to the axle, use anti-sieze on those studs. Trust me, you'll be glad you did...

 

[Kaw-Liga]

I just took off the front wheels and did some measuring/looking and moving the tire/wheel in and out a few inches. I'm going to go ahead and get a set(4) cause I don't want front the back to be different than one another 1.5" adapters. Steve, I understand why to use the anti-sieze, but shouldn't I use some thread locker too? can I use both together?

Rob

 

[Broncobowsher]

If you only need about 1/8" or so, get a set of used rotors off a Geo Tracker. Cut them at the hat (mid way between the rotor and the lug face) and toss the rotor. The ID of the Geo had just fits over the OD of the Ford rotor hat, bolt pattern is the same, perfect spacer.

 

[trophybass]

How much stud thread is the safe cut off point? I put some off the shelf 1/4" spacers from pepe boys after i did my COR steering conversion on my '76(the rims were hitting the TRE's). I have about 3/8-1/2" of stud to put the lug nuts on but i was considering getting longer studs just to be safe.

 

[Kaw-Liga]

I just ordered a set(4) adapters from ezaccessory on ebay
http://cgi.ebay.com/ebaymotors/Whee...ItemQQcategoryZ42614QQitemZ290091153881QQrdZ1
I got these 5 on 5.5 1.5" adapters four of them shipped is 133$ with 2-3 day service. I will need them for my TRO this weekend due to the fact that my 15x10 wheels with I think 3.75" bs on 76-77 knuckles is already just kissing the wheel weights on the inside lip. I figure 1/4" would be enough space, but those style spacers scare me. I also figures that I would get a slighty wider=more stable stance with my 5.5" sl and 36 swampers. This way I get what I need and then some and I feel safe doing it. These are the kind that you bolt to the hub using the existing studs then you bolt the wheel to the spacer with the pressed in studs on the spacer! So no need to worry about reaching enough threads. Another good thing is they should be at my house by Friday-just in time for my TRO instal. Also since the tires will stick out past the flares a little more I will throw that much more mud with my TSL's!

Rob

 

[ctowery]

How much stud thread is the safe cut off point? I put some off the shelf 1/4" spacers from pepe boys after i did my COR steering conversion on my '76(the rims were hitting the TRE's). I have about 3/8-1/2" of stud to put the lug nuts on but i was considering getting longer studs just to be safe.

Anything thats sticks past the end of the lug nut is waste. So as long as all the threads are used your fine.

Cary

 

[Steve]

Steve, I understand why to use the anti-sieze, but shouldn't I use some thread locker too? can I use both together?

Rob

No, do not use any thread locker. If you torque them correctly (~90 lbs-ft) with anti-sieze you'll be fine. The inner nuts that bolt the adapter to the axle will be hidden by the wheel and won't have drainage, so any water that gets in there will rust the nuts to the studs. Been there, done that.

 

[bronko69er]

How much stud thread is the safe cut off point? I put some off the shelf 1/4" spacers from pepe boys after i did my COR steering conversion on my '76(the rims were hitting the TRE's). I have about 3/8-1/2" of stud to put the lug nuts on but i was considering getting longer studs just to be safe.

Ready for a lot of math????
Here goes.

Area of major daimeter - Area of minor diameter = Area of 1 thread
[pi (1/2")^2 / 4] = .1963 sq. in. (major area)
-[pi (29/64")^2 / 4] = .1612 sq in. (area of bolt)
.1963-.1612 = .0351 sq.in. (area per thread)

Number of threads necessary to provide equal tensile area is,
Area of bolt / Area per thread
.1612 / .0351 = 4.59

Use saftey factor for ~60% thread engagement
100%/60% = 1.666 x 4.59 = 7.65 threads

On a 1/2-20 (20 threads per inch) 7.65 thread would be (7.65/20) or .3825" or a little over 3/8" MINIMUM!!!!!!!!

This would be the theoretical minimum needed to brake the bolt and not strip the threads under a static load. Introduce motion into the equation and things change. Do not use this if you life is on the line. I will not be held responsible as I am not a professional engineer. I'm just offering this as a guidline for bolt threading.

OK "cover my a$$" speech over.

Change these numbers around and you can use it for other bolt calcs too.

 

[trophybass]

Ready for a lot of math????
Here goes.

Area of major daimeter - Area of minor diameter = Area of 1 thread
[pi (1/2")^2 / 4] = .1963 sq. in. (major area)
-[pi (29/64")^2 / 4] = .1612 sq in. (area of bolt)
.1963-.1612 = .0351 sq.in. (area per thread)

Number of threads necessary to provide equal tensial area is,
Area of bolt / Area per thread
.1612 / .0351 = 4.59

Use saftey factor for ~60% thread engagement
100%/60% = 1.666 x 4.59 = 7.65 threads

On a 1/2-20 (20 threads per inch) 7.65 thread would be (7.65/20) or .3825" or a little over 3/8" MINIMUM!!!!!!!!

This would be the theoretical minimum needed to brake the bolt and not strip the threads under a static load. Introduce motion into the equation and things change. Do not use this if you life is on the line. I will not be held responsible as I am not a professional engineer. I'm just offering this as a guidline for bolt threading.

OK "cover my a$$" speech over.

Change these numbers around and you can use it for other bolt calcs too.

Holy SH!T, WOW and i suck at math. I think i've been thinking about getting the ones that Kaw-liga posted but i'm thinking about the 1" set that they have in their store. At least that way i know i will have enough stud and wont have any rubbing. Thanks for the math i WILL keep it for future reference. Thanks, Alex

 

[trophybass]

Anything thats sticks past the end of the lug nut is waste. So as long as all the threads are used your fine.

Cary

Thats part of my concern in the fact that since my lugnuts are enclosed on the ends i cant see how much thread i'm actually using, so its got me a little worried but its only about $50.00 to get a 1" set like kaw-liga got, so i think i'm gonna go that route just to keep it safe. Thanks guys.

 

[Kaw-Liga]

It was 133$ for 4(one on each wheel) shipped to my door, the ~50$ was for a set witch is only 2 adapters. I figured I'd get 4 so my front didn't stick out and my rear be narrow and all funny looking. Steve, thanks for clearing up my confusion about the anti-sieze!

Rob

 

[Goin Off Bronco]

This thread scares the be jesus out of me ! Use of spacers is a risk ! Adaptors are better as long as you get some that have a pilot for the center bore to load on. Adaptors are a technical piece, not just made..Lug centrics vs hub centric has been a looooong debate in my wheel profession. With Hub centrics winning today. In the aftermarket wheel industry you will find more that are Hub Centric now than before. Especailly with a huge leverage arm like 37", 38" tires. Stud length and thread engagement is critical to prevent wheel loss and or retention/torque. True that explained above that the adequate engagement is the disameter of the bolt/stud. Thread lubricants and or anti seeze is a NO !

 

[z70what]

Kaw Liga:

i want to see some pics of the stonecrusher tro and wheel spacers when you get it all installed... You're running the SAME setup that i'm getting ready to install, however my wheels have 4" backspacing...

Luke

 

[Kaw-Liga]

Luke, I'll be sure to take some before and afters. According to UPS tracking numbers my TRO should be at my door this afternoon. The spaces hopefully today but maybe tomorrow(1.5" is what I got) and if all is good to go by friday after work~5:30 then I will disassemble drill and assemble then saturday morning I will fine tune toe in and what not. I've just started hopeing that my tires don't stick out tooo much and look all hoopty like those lowered trucks with the tires way out to the side.

Rob

 

[Naildriver111]

I installed the Stone Crusher steering and 1 1/8" spacers last month, my wheels had 4 1/4" of backspacing. I really like the wider stance it has, and the way it drives now. I only have 1 tip for you, mount the center caps behind the spacer, they have a flange for the cap to rest in. I started with the rear wheels, and it was when I finished the first front one that I realized the hub locks weren't flush with the caps anymore, so I had the pleasure of remounting 3 spacers and wheels.

 

[Kaw-Liga]

Thanks for the tip on the center caps! I hadn't even thought of that and you just saved me some time and aggrivation.

Rob