Got some new wheels: Boss 338's in 20x10 and 20x8.5

[bk2minis]

So this seems like the place to ask a question about the boss 338's, so here goes.

Would these wheels be OK on a suburban with the load rating being so low?

I've got a 88 r20 (swapping to 5 lug) suburban silverado. Big block third row seating and every now and then I plan on filling the seats with people. As a side note it will never haul anything more than people.

I just love these wheels. I've tried to talk myself out of them and tried to find other wheels but the only other wheels I like are about $3000.
I've seen the Coys and the MB old-schools but I like the 338's better, but I guess if they won't hold up to the weight I'll have to go for the aforementioned wheels

[nlped]

Once you do the 1/2 ton swap stuff, you will run into the problem of them actually fitting the front. You need to read this thread before you make any decisions.
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[bk2minis]

Sorry should have clarified that as well.
This sounds like I'm being an a$$ but I'm not.
I know that there is an issue with the fit. I completely understand the problem with getting them to fit. That's why my question was for the "load rating" of the wheels.


So again I ask is this wheel strong enough to hold the weight of the suburban loaded with people?

I have weighed the options of other wheels not being an issue fitting but I really love these wheels. I also plan on upgrading to the mcgaughy 13" brakes so fitment should be ok
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[nlped]

Hey Man, no problem. Just wanted to be sure you were aware of the fitment issues. As far as load rating, you shouldn't have any issues with them at all. They have a higher load rating than most of the tires you can mount on them, especially if you plan on lowering it.

BTW, I too have the McGaughy kits front and rear and absolutely LOVE them, and the older part # 338's fit, so the price is even cheaper . I have had them on my Blazer for a few months now and have towed several car trailers, my boat and just generally driven the snot out of it with out issue. I say, if you plan on the McGaughy kit, go for it!!!

Ed

[bk2minis]

Good point about the tires. Thank you. You are the reason I even looked at the brake upgrade. It may be a while before I can get the brakes though. I'm trying to spend as little money as possible. My wife dubbed it project welfare. I'm gonna try to take it as far as possible without spending any money on it.

I took it on trade for a vw hoodride that I also traded for. It has great interior and soon to be freshly painted. The bodywork is being done by a guy who's frame I'm rebuilding after some shop hacked it to death. I sold the 22" wheels that came with the burb to buy paint and my parts truck to do the 5 lug swap. After the frame is done on the painters truck I'm body dropping a blazer for the wheels and some tools that I really need to make my garage complete (to me). Then I have a few other projects lined up to hopefully get bags. Fingers crossed
Goning to put 3/4 stuff under the parts truck and try to get my money back on that also
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[bajaracing]

Originally Posted by BossHogg69

finally got pics of the Boss 338s I had widened out for the rear of my truck (69 swb stepside).

fronts are regular grey 18x8's with 245/40's, in the rear I had 18x9.5's but they are now 18x12's with 335/30's. The work on the rear wheels was performed at Weldcraft wheels. The tires are BFG KDW2's I ordered through Tirerack.com.

Those 12s are SWEEET! Did you have to modify the bed wells? Is the rear axle stock width? Whats the backspace offset? So many questions, hope you don't mind.

[BossHogg69]

Originally Posted by bajaracing

Those 12s are SWEEET! Did you have to modify the bed wells? Is the rear axle stock width? Whats the backspace offset? So many questions, hope you don't mind.

The axle is a stock width '69 C10 12bolt that I swapped to 5 lug with stock length Moser axles (part# MSR-A3065GMT5) the backspace on the rear wheels is now 7.5", since I had the additional 2.5" added the the inside of the wheel (the b.s. was originally 5" with the 9.5" wheel). I have a stepside bed that will probably need to be tubbed a bit on the inside of the bed. The truck is blown apart now, but my plans are to take a set of fleetside tubs, cut them in half and graft them onto the inside of my bed. There is room to go wider (I have a lot of clearance between the frame and wheel), but a 335 tire is what I planned on, so a 12" wheel was what I went with.

As you can see, I still have a LOT of work to do...

[trkfrk]

I finally got my 18x8's and 20x10's last week.

[fast 95]

The rears have a defined lip like the grey and black ones do, but your fronts dont?

[mcbassin]

Originally Posted by trkfrk

I finally got my 18x8's and 20x10's last week.

Looks like a nice set up you have there. Are the new center caps any better than the old ones? Will you have to use adhesive/ silicone to keep the front ones on?

[ozman3803]

I might have missed but is it the 94.62 bore that is needed? Also what measurement is that measured in?
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[mcbassin]

Originally Posted by ozman3803

I might have missed but is it the 94.62 bore that is needed? Also what measurement is that measured in?
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Not sure which measurements you are looking for? Wheel bore? that looks like a mm dimension.

[ozman3803]

Yeah it was wheel bore in mm...thanks. the wheels come in different bore sizes on the elite wheels site so just wondering if the larger bore is a no mode needed wheel?
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[brossow]

Originally Posted by ozman3803

Yeah it was wheel bore in mm...thanks. the wheels come in different bore sizes on the elite wheels site so just wondering if the larger bore is a no mode needed wheel?
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Despite what may be shown on any website, the hub bore of the 338s in 5x5 hasn't changed since the first revision, at least not in any way that matters. They opened it up a bit on the inside for Rev 3 but not in a way that means anything for pre-'88 owners. These wheels (in 5x5) were designed for '88-up trucks and have never been marketed for or intended to properly fit older trucks. Various modifications (spacers, machine work on the hubs, etc.) may allow them to work, but the hub bore is irrelevant for older trucks as all revisions require such modifications on the front for all but light-duty (1" thick) rotors.

[ozman3803]

Gotcha, maybe I will order mine this summer and hopefully have them by this fall!
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[mcbassin]

Originally Posted by brossow

Despite what may be shown on any website, the hub bore of the 338s in 5x5 hasn't changed since the first revision, at least not in any way that matters. They opened it up a bit on the inside for Rev 3 but not in a way that means anything for pre-'88 owners. These wheels (in 5x5) were designed for '88-up trucks and have never been marketed for or intended to properly fit older trucks. Various modifications (spacers, machine work on the hubs, etc.) may allow them to work, but the hub bore is irrelevant for older trucks as all revisions require such modifications on the front for all but light-duty (1" thick) rotors.

Funny that they just don't even care about the pre 88 market. It just doesn't make sense. They could tweak them a little and make the wheels fit all 5X5 chevy trucks. I would buy another set though even though it takes a few hours to mod the rotors and caps.

[sixty8c10]

So, let me see if I understand all of this correctly. If I do the big brake upgrade (converting my front end to 5 lug), and convert my 68's rear axle to 5 lug these wheels will fit perfectly?

[brossow]

Originally Posted by sixty8c10

So, let me see if I understand all of this correctly. If I do the big brake upgrade (converting my front end to 5 lug), and convert my 68's rear axle to 5 lug these wheels will fit perfectly?

You couldn't have it much more wrong. You'll need a spacer at the rear because the backspacing is wrong (unless you manage to swap in an '88-up rearend) and you'll need to (1) machine down the front hubs, (2) use spacers up front, or (3) use light-duty rotors/spindles/calipers up front. These are absolutely not a straight bolt-on application.

[mcbassin]

What he said.

[AZChevyland]

I agree too! But its not hard to do.

[piecesparts]

We purchased a nearly new set of "338s" (20" X 10") for the back and (18" X 8.5") for the front of my Son's 86 Chevy truck. The wheels do have an issue with the center cap on the front hubs, on his truck (they are the 1.25 thick rotors). I understand that the thinner rotors have a different centre cap mounting, so they do not have the problem the thicker ones do. However we did some modifications to the wheel's center cap mounting tabs and shortened them a small amount (did not eliminate the catch on the tabs, just some of the material on the ends). I also did a flattening of the dust cap for the outer wheel bearings and made it flat on the end. The real issue is the tabs on the cap hits on the truck's dust caps flanged out edge where it seats on the hub. If you could get dust caps without the edge, then there would be no issue. The rims came off of a 92 Chevy truck and they had used 1/4" spacers on it. I put on a thinner spacer and the center cap is still seated and not pushed out. There is no backspacing issues with these rims on this model of Chevy truck, but I do not know about the earlier models.

Originally Posted by brossow

Despite what may be shown on any website, the hub bore of the 338s in 5x5 hasn't changed since the first revision, at least not in any way that matters. They opened it up a bit on the inside for Rev 3 but not in a way that means anything for pre-'88 owners. These wheels (in 5x5) were designed for '88-up trucks and have never been marketed for or intended to properly fit older trucks. Various modifications (spacers, machine work on the hubs, etc.) may allow them to work, but the hub bore is irrelevant for older trucks as all revisions require such modifications on the front for all but light-duty (1" thick) rotors.

[brossow]

Originally Posted by piecesparts

However we did some modifications to the wheel's center cap mounting tabs and shortened them a small amount (did not eliminate the catch on the tabs, just some of the material on the ends). I also did a flattening of the dust cap for the outer wheel bearings and made it flat on the end. The real issue is the tabs on the cap hits on the truck's dust caps flanged out edge where it seats on the hub. If you could get dust caps without the edge, then there would be no issue.

The Rev 3 version of this wheel (currently only available in 20") uses a completely different style of center cap that should eliminate this problem. The real issue is that the hub bore is too tight in critical places to allow the wheel to seat against the hub without a spacer (on the front).

In the rear, it depends on which width you get as to whether it will fit (disregarding "looking right") without a spacer. The 10" rim requires 1 1/2" to 1" spacer, depending on application. The 8" rim may fit fine without a spacer; I have no experience with this width and its accompanying backspacing.

[mcbassin]

Originally Posted by brossow

The 8" rim may fit fine without a spacer; I have no experience with this width and its accompanying backspacing.

The 8" wheels on the back of my son's 86 don't have the proper back spacing. They really need about 1-1.5" spacer on ea. side. I haven't put any spacers on it yet, hoping to find a pair of 10" wheels to match. It bothers me but not him.

[bcutt]

Originally Posted by BossHogg69

The axle is a stock width '69 C10 12bolt that I swapped to 5 lug with stock length Moser axles (part# MSR-A3065GMT5) the backspace on the rear wheels is now 7.5", since I had the additional 2.5" added the the inside of the wheel (the b.s. was originally 5" with the 9.5" wheel). I have a stepside bed that will probably need to be tubbed a bit on the inside of the bed. The truck is blown apart now, but my plans are to take a set of fleetside tubs, cut them in half and graft them onto the inside of my bed. There is room to go wider (I have a lot of clearance between the frame and wheel), but a 335 tire is what I planned on, so a 12" wheel was what I went with.

As you can see, I still have a LOT of work to do...

Man this set up is bad a$$!! What drop are you running front/rear? I want to go with the same look for my 72 and you nailed it

[BossHogg69]

Gonna start with a 4.5/6 for now (I have CPP 2.5" spindles and 2" springs, with 6" springs and a c-notch out back, but I imagine I'll end up adjusting it a bit to get the fenders right above the tops of the tires. The back tires are about a half inch taller than the fronts, as I like a little bit of 'rubber rake' on my dropped trucks. I may go an additional .5" f/r to make it 5/6.5, but I'll only know for sure after I get the engine back in and the body on it. I do know that those 335's will be screaming for mercy when I unleash my aluminum headed solid roller 468" BBC and the TKO 5 spd on them! Here's another pick of it out in the light.