You need to know the amount of interference fit between the stud with the straight knurl and the hole ID. If it's only .010 or less, you can drive them in from the back with a hammer (if you have the room) or possibly use some washers and the nuts to draw them through to seat them. That would mean purchasing the studs and measuring everything.

You might want to inquire with the mfg again. If they drilled them for threads, chances are they are sized for the minor diameter of the proposed threads, not the diameter for the press in studs. Two different things.

Yup, just took a caliper to the holes and they are indeed drilled for a tapped thread. Thought that was too easy a solution. Panic also just emailed and also nixed the idea for the same reason. They are looking into solutions and will report back tomorrow.

Yes, I'd go with studs anyway. You'll need to know the hole size to get the correct knurl size. If they sent you GSL-SE axels, the axle themselves are a bit longer. Before doing anything, validate the bolt pattern of what you got first.

No go on studs. Wrong size holes, drilled for thread tapping size. I did check length and bolt pattern before install and all is good. Just never thought to check threads.

Maybe Panic could send you a tap set, or reimburse you for one? It's really not hard to tap threads with the right tools. It's not ideal but might be your best course at this point.

Good luck!

Tried that with my Harbor Freight tap set. Couldn’t get the tap to bite. Maybe more thread chasers than thread taps? Maybe pulling the axle, and setting it up in my drill press with a decent tap would work. Will wait on Panic’s ideas tomorrow.

Quick update. Panic sent a shipping label. Axles are going back to be tapped.

Now that's service.

Yeah he seems super responsive, very rare these days! Glad you got it worked out.

as banzai mentiond. or even could use the nut and stack of washers to pull it into the hole.

Ok, on to next problem.

Panic axles are now threaded and back with me. Installed again, and they sit too far out to clear the brake mount. Shoulder on Panic axle is taller than the OEM shoulder. Wondering if I should omit the spacer but then bearing would sit against the radius machined in to the shoulder. (The OEM spacer is beveled to clear any radius in the shoulder).

Got an email in with Panic.

But in the meantime. Any variation in big bearing 4x110 axles that would explain this? I believe disc brake 4x110 big bearing means 84 or 85 GSL, but saw somewhere that there may have been a bastard 83 version?


https://cimg2.ibsrv.net/gimg/www.rx7...ad79501df.jpeg
https://cimg3.ibsrv.net/gimg/www.rx7...d44c458cf.jpeg
https://cimg4.ibsrv.net/gimg/www.rx7...61eef42c7.jpeg
https://cimg5.ibsrv.net/gimg/www.rx7...6ec9e8eee.jpeg
https://cimg6.ibsrv.net/gimg/www.rx7...b73921b1f.jpeg

Heard back from Panic in seconds! Excellent service. Yes, you just omit the spacer. Issue is with the Rock Auto bearings I sourced…. They lack the chamfer that the OEM bearings have to clear the radius.

https://cimg3.ibsrv.net/gimg/www.rx7...635b53fc9.jpeg
https://cimg4.ibsrv.net/gimg/www.rx7...8d98fac06.jpeg

Interesting, I thought the spacer on the OEM axle was so the bearing doesn't need a fillet edge.
It's good to hear Panic is being so responsive, I'm starting to feel bad for posting the link.

What is the thickness of the spacer? And I think you need to use the spacer for the reasons you stated.

When I was doing Moser axles through RE Speed (the second owner) I decided to use GSL style axles because the are 10mm shorter per side that GSL/SE axles. I did this for tire clearance because I needed to be able to fit an 8" wide wheel on a lowered car with OE fenders (SCCA Rules.....). The ones I got were exactly the same as the OE GSL axles I had laying around just beefier.

I do not believe there was a length difference between Small bearing and Big bearing GSL axles. I ran both varieties on my race car with OE axles and never saw a difference,

Maybe Panic is producing one length of axle with the only variation being the flange - GSL or GSL/SE? The work around for you would be to space the caliper bracket out from the housing mount until it is centered on the rotor.

Cut the bearing and spacer off the Panic axle and reinstalled with the other bearing I had left and with no spacer. (Dremeled a chamfer on the bearing to clear the small radius on the axle were the bearing seats). Disc rotor and brake now appear to line up well.

Replacement bearing for the other side arriving early next week. Will report back when installed and tested.

Done! New axles installed and test driven. No thwick thwick thwick noise. Mission accomplished.

Glad to hear this saga ending well.
Did you end up carving a chamfer in both bearings or did you go OEM?

Chamfer on left and right bearing. Probably overkill, but given the amount of metal on that inner race I believed dremeling a chamfer could do no harm.

Late to this... I've been working on measuring a GSL and an -SE big bearing axle for 82Transam for a while now in my off time. The thought was to send the model with the proper bearing tolerances on a drawing to moser instead of filling out all the information on their sheet. The one thing left is to measure out enough samples to get confidence on the OD nominal and tolerance band of the press fit bearing race of the OEM. I think I have 5-7 floating around. All of those have been within a few tenths of a thou of each other. Once that's done I'll be happy to share the 3d model in whatever format.