5x4.5" on the big GM rear uprights

[pmbrunelle]

So the wheel bearings that come on these things are 5x115. Damn metrification...

Can't the bearings be easily converted to 5x4.5" for better choice in wheels?

It seems like if you machined oversized lug stud holes shifted 0.35 mm towards the axle, you could simply press in studs with an oversized knurling diameter.

This seems too easy. Am I missing something here? I haven't seen this done on the Fiero forums.

[ericjon262]

Will found some wobble lug nuts that allow for minor differences in wheel pattern at some point. Obviously, something like that requires a proper counterbore and register on the hub, but would work. if I can find his post I'll get the PN, maybe he remembers where it was?

[pmbrunelle]

I remember the wobble nuts, and while I'm sure they work, I just find it's not an OEM-clean solution.

[ericjon262]

that's fair. I would say the other option would be to press the studs out and have the hub redrilled, or you could try and adapt non GM hubs.

[The Dark Side of Will]

Ignoring the difference is also an option. AutoXers interchange BMW (5x120) and Corvette/GM (5x120.65) wheels more often than my perfectionism wants to admit. That's about the same as the difference between 5x115 and 5x114.3.

That being said, all the large pattern GM bearings of the last 30 years or more have the same external form factor. Take the A-body knuckles for the 5x115 bearings, drill the bolt holes out and spot face the holes on the back side and C5/6/7 rear wheel bearings (and 2000's W-body, etc) will bolt right up...

[ericjon262]

I almost said that too, it's only 0.35mm of difference from the centerbore to the stud, and that's assuming the studs are even machined that precisely.

[pmbrunelle]

I almost said that too, it's only 0.35mm of difference from the centerbore to the stud, and that's assuming the studs are even machined that precisely.

We throw around 0.1 mm position tolerance for holes like it's candy. Any less than that will raise eyebrows.

For those unfamiliar with ASME Y14.5, it means that the axis of the hole should lie within a cylinder having a 0.1 mm diameter.

I think I like the solution of converting the knuckles for later hubs. Hubs are a semi-wear part... it's nice to be able to bolt on wear parts as-is off the shelf.

[ericjon262]

We throw around 0.1 mm position tolerance for holes like it's candy. Any less than that will raise eyebrows.

For those unfamiliar with ASME Y14.5, it means that the axis of the hole should lie within a cylinder having a 0.1 mm diameter.

I think I like the solution of converting the knuckles for later hubs. Hubs are a semi-wear part... it's nice to be able to bolt on wear parts as-is off the shelf.

well, another option would be to look at mustang bearings, IIRC, they use 5x4.5 and should be a larger bearing compared to fiero parts. they also have the advantage of being available anywhere.

Edit:

maybe not, looks like they use a 4 bolt pattern...

[ericjon262]

another possibility is the Chevy Captiva, according to this it uses 5x4.5 as well. The city express bearing is way wrong.

https://www.wheel-size.com/pcd/5x114.3/

https://www.amazon.com/Assembly-Compati ... B07LFGFHQY

[The Dark Side of Will]

another possibility is the Chevy Captiva, according to this it uses 5x4.5 as well. The city express bearing is way wrong.

https://www.wheel-size.com/pcd/5x114.3/

https://www.amazon.com/Assembly-Compati ... B07LFGFHQY

Is that a European or Chinese market website?

Jeep uses 5x4.5 and a bunch of the older bearings look a whole lot like GM bearings.

Jeep and GM tend to pull from the same parts bins in a number of cases; GM and Ford much less so. Spline and CV joint compatibility is important and may not work between GM and Ford.

[The Dark Side of Will]

We throw around 0.1 mm position tolerance for holes like it's candy. Any less than that will raise eyebrows.

For those unfamiliar with ASME Y14.5, it means that the axis of the hole should lie within a cylinder having a 0.1 mm diameter.

I think I like the solution of converting the knuckles for later hubs. Hubs are a semi-wear part... it's nice to be able to bolt on wear parts as-is off the shelf.

What aspect of the discussion are you relating to the hole tolerance?

[pmbrunelle]

We throw around 0.1 mm position tolerance for holes like it's candy. Any less than that will raise eyebrows.

For those unfamiliar with ASME Y14.5, it means that the axis of the hole should lie within a cylinder having a 0.1 mm diameter.

I think I like the solution of converting the knuckles for later hubs. Hubs are a semi-wear part... it's nice to be able to bolt on wear parts as-is off the shelf.

What aspect of the discussion are you relating to the hole tolerance?

I edited that post of mine with a quote to reflect the statement I was going off of.

ericjon262 was suggesting that a 0.35 mm error seems small, and might be within the typical drilling tolerance of the stud hole position in the hubs.

I then shared that 0.1 mm was rather inexpensive enough (looser would not imply major cost savings), so I would be surprised if the tolerances were that loose on the hubs. Doesn't mean the tolerances aren't that wide, but it sounds big.

[ericjon262]

I edited that post of mine with a quote to reflect the statement I was going off of.

ericjon262 was suggesting that a 0.35 mm error seems small, and might be within the typical drilling tolerance of the stud hole position in the hubs.

I then shared that 0.1 mm was rather inexpensive enough (looser would not imply major cost savings), so I would be surprised if the tolerances were that loose on the hubs. Doesn't mean the tolerances aren't that wide, but it sounds big.

I guess I was meaning that I have a hard time believing that a 5x114.3 wheel won't easily slide over 5x115 studs and function without problems. The lugs shouldn't center the wheel, all they do is hold it to the flange, and if we assume the tolorances stack, 0.1mm inboard on the wheel and 0.1mm outboard on the hub, now the total error is even less, down to 0.15mm obviously it's not that convenient, but I would be interested in seeing just how precise the holes are on both components.

[ericjon262]

another possibility is the Chevy Captiva, according to this it uses 5x4.5 as well. The city express bearing is way wrong.

https://www.wheel-size.com/pcd/5x114.3/

https://www.amazon.com/Assembly-Compati ... B07LFGFHQY

Is that a European or Chinese market website?

Jeep uses 5x4.5 and a bunch of the older bearings look a whole lot like GM bearings.

Jeep and GM tend to pull from the same parts bins in a number of cases; GM and Ford much less so. Spline and CV joint compatibility is important and may not work between GM and Ford.

Not sure, I just googled "wheels with 5x114.3" and that list came up. The Jeep idea is a good one, they'll likely remain available long term too. As far as CV axle splines go, I think it wouldn't be too hard to have a new shaft cut with the correct splines, to join the tripot to the any outer CV. Not necessarily cheap, but doable.

[FieroWanaBe1]

Late to the show:
Crown makes these:
https://www.amazon.com/dp/B00B8X2INK/re ... 00_TE_item
Rebuildable race inserts

From Timkin on their interchange:
Bolt Circle Diameter B (in) 4.500
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75
Brake Pilot Dia (in) 2.828
Driven_Non Driven Driven
Flange (#) 2.000
Flange Diameter (in) 5.669
Flange Offset (in) 1.811
Flange Shape Modified
Generation Type 1
Hub Pilot Dia G (in) 3.937
Roll Form (Y) N
Spline Quantity 27.000
Wheel Pilot Dia (mm) 71.300
Wheel Studs (Y/N) Y
Wheel Stud Qty 5.000
Wheel Stud Size (in) 43832.000

From Timken on the S10 4WD fromn Hub:
Bearing Type BALL
Bolt Circle Diameter B (in) 4.750
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75
Brake Pilot Dia (in) 2.780
Driven_Non Driven Driven
Flange (#) 2.000
Flange Diameter (in) 5.689
Flange Offset (in) 1.861
Flange Shape Modified
Generation Type 3
Hub Pilot Dia G (in) 3.209
Roll Form (Y) N
Spline Quantity 27.000
Wheel Pilot Dia (mm) 70.100
Wheel Studs (Y/N) Y
Wheel Stud Qty 5.000
Wheel Stud Size (in) M12X1.5

[The Dark Side of Will]

Late to the show:
Crown makes these:
https://www.amazon.com/dp/B00B8X2INK/re ... 00_TE_item
Rebuildable race inserts

From Timkin on their interchange:
Bolt Circle Diameter B (in) 4.500
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75
Brake Pilot Dia (in) 2.828
Driven_Non Driven Driven
Flange (#) 2.000
Flange Diameter (in) 5.669
Flange Offset (in) 1.811
Flange Shape Modified
Generation Type 1
Hub Pilot Dia G (in) 3.937
Roll Form (Y) N
Spline Quantity 27.000
Wheel Pilot Dia (mm) 71.300
Wheel Studs (Y/N) Y
Wheel Stud Qty 5.000
Wheel Stud Size (in) 43832.000

From Timken on the S10 4WD fromn Hub:
Bearing Type BALL
Bolt Circle Diameter B (in) 4.750
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75
Brake Pilot Dia (in) 2.780
Driven_Non Driven Driven
Flange (#) 2.000
Flange Diameter (in) 5.689
Flange Offset (in) 1.861
Flange Shape Modified
Generation Type 3
Hub Pilot Dia G (in) 3.209
Roll Form (Y) N
Spline Quantity 27.000
Wheel Pilot Dia (mm) 70.100
Wheel Studs (Y/N) Y
Wheel Stud Qty 5.000
Wheel Stud Size (in) M12X1.5

What's the original application for these?

[The Dark Side of Will]

I edited that post of mine with a quote to reflect the statement I was going off of.

ericjon262 was suggesting that a 0.35 mm error seems small, and might be within the typical drilling tolerance of the stud hole position in the hubs.

I then shared that 0.1 mm was rather inexpensive enough (looser would not imply major cost savings), so I would be surprised if the tolerances were that loose on the hubs. Doesn't mean the tolerances aren't that wide, but it sounds big.

I guess I was meaning that I have a hard time believing that a 5x114.3 wheel won't easily slide over 5x115 studs and function without problems. The lugs shouldn't center the wheel, all they do is hold it to the flange, and if we assume the tolorances stack, 0.1mm inboard on the wheel and 0.1mm outboard on the hub, now the total error is even less, down to 0.15mm obviously it's not that convenient, but I would be interested in seeing just how precise the holes are on both components.

Also, the hole locations and the lug stud angles are different things. Slight mismatches between the wheel and hub can be taken up by slightly cocking the lug studs in their knurled holes. It's pretty red-neck, but as I noted above, works more often than my perfectionism wants to admit.

[FieroWanaBe1]

What's the original application for these?

JEEP CHEROKEE 1984-1989
JEEP COMANCHE 1986-1989
JEEP WRANGLER 1987-1989

[The Dark Side of Will]

I haven't checked, but there's also a good chance that AMC Eagle front hubs would work in one of the GM large pattern knuckles.

The AMC Eagle hubs are 5x4.5 with 27 spline outer CVs. I $$ume these are the same or compatible with GM 27 spline outer CVs from the '80's mid-sized FWD cars. I haven't looked at the knuckle interface compatibility, though.

Eagle hubs use a tapered roller bearing pair and are rebuildable.

[The Dark Side of Will]

Late to the show:
Crown makes these:
https://www.amazon.com/dp/B00B8X2INK/re ... 00_TE_item
Rebuildable race inserts

From Timkin on their interchange:
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75

Hub Pilot Dia G (in) 3.937

From Timken on the S10 4WD fromn Hub:
Bearing Type BALL
Bolt Circle Diameter H (in) 4.750
Bolt Quantity 3.000
Bolt Size (in) M12x1.75

Hub Pilot Dia G (in) 3.209

JEEP CHEROKEE 1984-1989
JEEP COMANCHE 1986-1989
JEEP WRANGLER 1987-1989

The "H" bolt circle on the GM FWD hardware (including the C5/6/7 Corvette rear bearings) is 116mm, so that's different than these.
I have a couple of knuckles that I can measure for the larger knuckles. The A-body 27 spline setup has a 90.1mm bore in the knuckle. That's a lot smaller than the 100mm hub pilot on the Jeep units. Also on the S10 hub, the 3.209 diameter steps up to a diameter larger than 90, so that aspect requires modifying the FWD knuckles as well.