TheGrrrrr's 1994 80 Series Build Thread - "The Notorious B.G.E." (5 Viewers)

[TheGrrrrr]

I first noticed mine when looking into the DS footwell with the hood up, and I saw daylight beneath the truck.

Daylight. Ordered a bushing kit. I think it goes there.

 

[LongDuck]

Pro-Tips:

1) the steering shaft has 2× U-joint halves which will need to be loosened, slid toward the driver for working room, and rotated 90deg to clear the rag-joint. Secure the steering wheel so it doesn't spin, breaking the horn and airbag wiring harnesses.
B) the rag-joint has a rubber spacer in between the two plates, and each plate has studs which must line up when you align the bolt holes (2×10mm). Use a Sharpie to scribe a line across the splined shaft BEFORE you remove the connection, so it goes back where it started with your steering wheel straight.
III) leave the firewall bolts for the rubber seal LOOSE until you get it all hooked up again and then rotate the steering wheel while watching for oblong movement of the steering shaft in the seal - if there's a lot of motion, this seal won't survive long, but there's not much you can do about it. Tighten the gasket bolts lightly, as this isn't a submarine thru-hull fitting, it's just a dust and dirt gasket...
Four) once you've done this a few times, you can do the whole job in about 10 minutes. Since this is your first time, it'll take about an hour or so.
Cinco) make an appointment with your chiropractor TODAY so you won't have to wait so long for an appointment.

Good luck!

 

[TheGrrrrr]

Pro-Tips:

1) the steering shaft has 2× U-joint halves which will need to be loosened, slid toward the driver for working room, and rotated 90deg to clear the rag-joint. Secure the steering wheel so it doesn't spin, breaking the horn and airbag wiring harnesses.
B) the rag-joint has a rubber spacer in between the two plates, and each plate has studs which must line up when you align the bolt holes (2×10mm). Use a Sharpie to scribe a line across the splined shaft BEFORE you remove the connection, so it goes back where it started with your steering wheel straight.
III) leave the firewall bolts for the rubber seal LOOSE until you get it all hooked up again and then rotate the steering wheel while watching for oblong movement of the steering shaft in the seal - if there's a lot of motion, this seal won't survive long, but there's not much you can do about it. Tighten the gasket bolts lightly, as this isn't a submarine thru-hull fitting, it's just a dust and dirt gasket...
Four) once you've done this a few times, you can do the whole job in about 10 minutes. Since this is your first time, it'll take about an hour or so.
Cinco) make an appointment with your chiropractor TODAY so you won't have to wait so long for an appointment.

Good luck!

I'm sure @Cruiserhiggs will fit better than I will. I'll add it to his list.

 

[tbisaacs]

Fine I guess I’ll follow both your build threads

 

[TheGrrrrr]

My thinking around wheels has been a work in progress and I think I've worn out the search button. This is my build thread, so y'all can keep the extremely helpful 'Use the search function' comments in their holster. I'm thinking out loud here. It seems like there are two schools of thought on backspacing for running 37" tires:

1. Center the backspace, which I take to mean on a 9 inch wide wheel you would have a 4.5" backspace. In most cases this seems like it would require the use of spacers to get the best placement. Not sure what the practical beneift is here, but feels like its one of those human derived preferences based on our natural love of symmetry. Would love some data on why this approach is objectively better or worse than any other. The many opinions on spacers not withstanding. Haven't found that yet.
2. Avoid spacers at all costs by determining the backspace based on the final geometry of the build that will allow fitment with zero or minimal rubbing. With my truck not having flares, this seems to favor less backspace as a means to clean fitment with the tire pushed further away from the truck. Maybe 3.5" backspace? This seems like it would require experimentation, which could get expensive.

With all the choices and apparent need for experimentation to determine what is best on any given rig, my thinking is that I should go with cheap steelies in 17x9 at either a centered or a targeted backspacing and work from there.

The Pro Comp 97's only have a 2000lb load rating, which seems low, so I'm leaning towards these Black Rock Wheel 997's which have a 3000lb load rating and are a matte black (bonus). They are available in the following 17" options:

If my thinking is correct, the only viable option of these is the 'centered option' of 17x9 at 4.5" of backspace, because the others are moving in the wrong direction at 4.5" on an 8" wide wheel and 5" on a 9 inch wide wheel. I think I would need a yet to be determined width spacer to accommodate.

I woke up thinking about this and am pretty sure I'm not confident in my thinking here, so really just working it through. Input welcome.

 

[Somebodyelse5]

My thinking around wheels has been a work in progress and I think I've worn out the search button. This is my build thread, so y'all can keep the extremely helpful 'Use the search function' comments in their holster. I'm thinking out loud here. It seems like there are two schools of thought on backspacing for running 37" tires:

1. Center the backspace, which I take to mean on a 9 inch wide wheel you would have a 4.5" backspace. In most cases this seems like it would require the use of spacers to get the best placement. Not sure what the practical beneift is here, but feels like its one of those human derived preferences based on our natural love of symmetry. Would love some data on why this approach is objectively better or worse than any other. The many opinions on spacers not withstanding. Haven't found that yet.
2. Avoid spacers at all costs by determining the backspace based on the final geometry of the build that will allow fitment with zero or minimal rubbing. With my truck not having flares, this seems to favor less backspace as a means to clean fitment with the tire pushed further away from the truck. Maybe 3.5" backspace? This seems like it would require experimentation, which could get expensive.

With all the choices and apparent need for experimentation to determine what is best on any given rig, my thinking is that I should go with cheap steelies in 17x9 at either a centered or a targeted backspacing and work from there.

The Pro Comp 97's only have a 2000lb load rating, which seems low, so I'm leaning towards these Black Rock Wheel 997's which have a 3000lb load rating and are a matte black (bonus). They are available in the following 17" options:

View attachment 3492533

If my thinking is correct, the only viable option of these is the 'centered option' of 17x9 at 4.5" of backspace, because the others are moving in the wrong direction at 4.5" on an 8" wide wheel and 5" on a 9 inch wide wheel. I think I would need a yet to be determined width spacer to accommodate.

I woke up thinking about this and am pretty sure I'm not confident in my thinking here, so really just working it through. Input welcome.

Centered rubs less. Clears the fender, rubs in tub at full bump, mostly clears pinchweld (the L arms will correct this).

More poke generally means more rubbing, pinchweld and fenders. If you’re going to cut, this doesn’t matter. Or if you don’t care about rubbing, send it.

I got summit’s because they offer a 9” width wheel with 4.5” bs. Method doesn’t.

 

[JunkCrzr89]

Centered rubs less. Clears the fender, rubs in tub at full bump, mostly clears pinchweld (the L arms will correct this).

More poke generally means more rubbing, pinchweld and fenders. If you’re going to cut, this doesn’t matter. Or if you don’t care about rubbing, send it.

I got summit’s because they offer a 9” width wheel with 4.5” bs. Method doesn’t.

That’s the truth . Also, @GW Nugget did a ton of an experimenting to figure out the ideal backspacing for stuffing 37x12.50 with low lifts (<3”). His build thread has like 5 years worth of trial and error.

 

[baldilocks]

17x9 with 4.5 BS will indeed require are spacer to keep the tire off the radius arm. If you want to keep off the radius arm/inner fender and also keep the outboard edge of the tire tucked inside the uncleared fender your going to e disappointed.

Shape of the tire has a lot to do with this formula also. All of the experimentation has been done.

 

[JunkCrzr89]

17x9 with 4.5 BS will indeed require are spacer to keep the tire off the radius arm

You mean a 8” wide w/ 4.5 BS will require a spacer, right? 4.5 BS on a 9” wide wheel is centered.

 

[Somebodyelse5]

17x9 with 4.5 BS will indeed require are spacer to keep the tire off the radius arm. If you want to keep off the radius arm/inner fender and also keep the outboard edge of the tire tucked inside the uncleared fender your going to e disappointed.

Shape of the tire has a lot to do with this formula also. All of the experimentation has been done.

I am running a 9” wide wheel with 4.5” backspacing with 37x12.5 BFG KM3’s and with no spacers… no radius arm rubbing

 

[TheGrrrrr]

I am running a 9” wide wheel with 4.5” backspacing with 37x12.5 BFG KM3’s and with no spacers… no radius arm rubbing

How much of that do you attribute to BFG tending toward being smaller than advertised vs the setup providing acceptable margins?

 

[JunkCrzr89]

How much of that do you attribute to BFG tending toward being smaller than advertised vs the setup providing acceptable margins?

I’m running a 7.5” wide wheel that, with 1” spacers, nets me 3.75” backspacing, and my 37x12.5r17 Goodyear MTRs (which are true to size at 36.9”) don’t rub the radius arms or outer fender lips. Running a setup in which the wheel mounting surface is centered with the wheel width (i.e. 0 offset) is the key.

From GW Nugget regarding wheel specs to run 37s on low lifts (<3”):

9” wide wheel = 4.5” backspacing
8.5” wide wheel = 4.25” backspacing
8” wide wheel = 4” backspacing
7.5” wide wheel = 3.75” backspacing

 

[Somebodyelse5]

How much of that do you attribute to BFG tending toward being smaller than advertised vs the setup providing acceptable margins?

idk if someone wants to slap a different offset and brand on there, we can test it out and see

 

[TheGrrrrr]

idk if someone wants to slap a different offset and brand on there, we can test it out and see

I think I found a set of used Ridge Grapplers in 37x12.5/17 that I will pick up for testing purposes. Probably going to order the Black Rock steelies in 17x9 at 4.5" BS to pair up with them as a starting point. Its sounds like that should be close to a winning combination, and at least a jumping off point for adjusting with a spacer or otherwise.

 

[landtank]

A 9” rim with 4.5” back spacing means you have an offset of 1/2”.

Our factory rims have 0” offset , so a 9” rim would have 5” back spacing to meet that same offset.

 

[kcjaz]

Fine I guess I’ll follow both your build threads

Ditto. I've all but convinced myself that the next mod for the 200, after completing current rebuild project, is an 80. For now, I'll live vicariously through you.

 

[TheGrrrrr]

A 9” rim with 4.5” back spacing means you have an offset of 1/2”.

Our factory rims have 0” offset , so a 9” rim would have 5” back spacing to meet that same offset.

Thats an interesting way of looking at it and I think part of the 'aha' I've been seeking. If what @Somebodyelse5 is running works but right up on the arms, then he should have a minimum of 1/2" of room on the outboard side because he has given it up on the inboard side. A 5" Backspace would get back the 1/2" of clearance inboard but would cost that much outboard, where I don't yet know how much I can give up.

Am I thinking about this right?

 

[baldilocks]

You mean a 8” wide w/ 4.5 BS will require a spacer, right? 4.5 BS on a 9” wide wheel is centered.

It’s still 4.5”. A 1” spacer will work. I eliminated the 1” spacers when I bought wheels with 3.5” bs.

 

[baldilocks]

I am running a 9” wide wheel with 4.5” backspacing with 37x12.5 BFG KM3’s and with no spacers… no radius arm rubbing

Were 37’s on the truck when you bought it?

 

[Somebodyelse5]

Were 37’s on the truck when you bought it?

Nope. It was factory