gt14rider 795 #1 Posted January 18, 2023 Hi all, been working on a lsd out of a 73 auto 12, while cleaning up the bull gear I noticed what looks like a couple of cracks, I can't feal it if you run finger nail over it, looks to go all the way around . Anyone ever have a bull gear crack. Share this post Link to post Share on other sites
oldlineman 1,482 #2 Posted January 18, 2023 That can be checked, not sure what it's called but welders use the process. Someone with greater knowledge than I will respond. Possibly a machine shop could test it for you, looks like a crack to my untrained eye though. Bob Share this post Link to post Share on other sites
pfrederi 17,856 #3 Posted January 18, 2023 Does the apparent crack line up with the break in the the core shown in your other posting?? I think you may need to replace your differential.. 4 Share this post Link to post Share on other sites
Pullstart 63,081 #4 Posted January 18, 2023 1 hour ago, oldlineman said: That can be checked, not sure what it's called but welders use the process. Someone with greater knowledge than I will respond. Possibly a machine shop could test it for you, looks like a crack to my untrained eye though. Bob Magnaflux? 2 1 Share this post Link to post Share on other sites
daveoman1966 3,758 #5 Posted January 19, 2023 (edited) Any repair effort is like to be futile. I have a replacement bull gear from a LSD that I tore apart for the pinion gears. I'll put it in your mailbox for $52... SHIPPED. Here it is...unscathed. I accept Paypal or Money order... Paypal account name is: daveoman@windstream.net I Edited January 19, 2023 by daveoman1966 3 Share this post Link to post Share on other sites
8ntruck 7,079 #6 Posted January 19, 2023 Magnaflux is one method, though you need access to the equipment. NAPA has a florsent dye that will be absorbed by a crack, and will make the crack show up under UV light. Dye pennetrant is another method. This is a dye that will soak into a crack then make it show up when a white powder is sprayed over it. Share this post Link to post Share on other sites
daveoman1966 3,758 #7 Posted January 20, 2023 Realizing $52 is too much for this bull gear I'll knock off $20.... Making it $32...SHIPPED flat rate USPS. If you or anyone else wants it, send Paypal money as "Family & Friends"... My Paypal account name is: daveoman@windstream.net 2 Share this post Link to post Share on other sites
gt14rider 795 #8 Posted January 20, 2023 Thanks Dave, I purchased one from K&B, along with the body core. I will keep you in mind if I need something else. Thanks for the response. Share this post Link to post Share on other sites
gt14rider 795 #9 Posted January 20, 2023 On 1/18/2023 at 2:59 PM, pfrederi said: Does the apparent crack line up with the break in the the core shown in your other posting?? I think you may need to replace your differential.. @pfrederiThere seems to be two cracks in the bull gear, but one does come close to the body core crack Share this post Link to post Share on other sites
pfrederi 17,856 #10 Posted January 20, 2023 There is a lot of stress on these parts and failure can cause a broken tranny case among other issues. I would not risk using them...to me both parts are scrap... 2 Share this post Link to post Share on other sites
gt14rider 795 #11 Posted January 20, 2023 Got both coming from K&B. Next 1533 and new spring, repairing parking brake. 1 1 Share this post Link to post Share on other sites
