Hi Forum, I have a 58 GMC truck with a six cylinder 270 motor. The ring gear is heading south. Does anyone have a source, or know the part# or have any ideas?? Thanks, -Steve
Big Old 270 Cid You may want to check out KANTER of Boonton, New Jersey. They list all GMC's even the V6 305, I had that one in my 61 panel wagon, what a engine. Good Luck www.kanter.com
GMC Master Parts Book shows many flywheel/ring gear combos for '58 270 engines. 8614887 for Hydra-Matic flywheel 2343767 for 10" clutch 2343769 for 11" clutch 2383743 for 13" clutch 2362231 for TorqueMatic Once you figure out which you need try advertising for it over on the OldGMCTrucks web site at http://oldgmctrucks.infopop.cc/eve/forums/a/frm/f/4266021295 These guys live and breathe GMC long motors.
clutch size Thanks Guys for the good info. I have a 4 speed manual trans, does that mean I have a specific size clutch?? Or could it be any of the 3? Thanks, -Steve
The 13" clutch was a big truck (450 and up) item. I don't know how to tell the difference between the 10 and 11 other than with a ruler. GMC Maintenance Manual says the 10" was standard on 6 cylinder engines and the 11" was an option.
Turns out the ring gear is replaceable (I didn't know that) and that all 56-62 270" engines (no matter 10" or 11" clutch) use 2343768: 168 tooth, 12 volt ring gear.
Ring Gear Steve ; First thing , go find a commercial brake shop , the kind of place that re-lines brake shoes, rebuilds clutches and grinds flywheels etc. ~ they'll be able to press the old one off and the new one back on but best of all , they'll prolly have your new ring gear , in stock . If i turns out to be a really oddball , unobtanium one , they can mark it , press it off , rotate it 90° in the direction the engine turns and re-install it , this will work for years to come as the engine always comes to rest in the same position (hence why it wears in one place) so rotating the ring gear 90° allows the starter's Bendix to engauge just after the damaged bit and by the time the damaged bit comes 'round , the Bendix is full meshed so there's no problem . This is not some therory , it's a dealer trick I learned 40 years ago and have been using ever since , never failed .
I'd like to update this thread. I was able to order a ring gear, so the truck is apart. The gear is about 1/4 " too wide (id). Was able to order a flywheel; had same bigger ring gear, and wrong mounting pattern. The id on my ring gear is 13". Found a manufacturer in India, and looked through their parts list- no 13" id 168 tooth, just 13.26" id. Flipped and rotated my flywheel (which had already been flipped), still messed up. I'm going to try to find another source, and think about machining the new flywheel to fit but I don't know about the extra 1/4" width????
You might try checking over on http://oldgmctrucks.infopop.cc/eve Those guys live for GMC six cylinder engines.
Thanks to you who tried to help. Once I had the correct id and tooth count, my friend who ordered the first ring gear was able to order the correct one (for my truck). Good to go; keep on truckin' etc. -Steve ps. my mistake was trying to order the gear before disassembly
Steve: Do the forum a favor by letting us know where you got the ring gear. We are always looking for places to buy parts for our 50+ year old trucks.
