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| | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | 1957 Chevrolet 5700 LCF two ton. I have the shop manual for 1957 trucks but of course it has no part number listings. I do not have the assembly manual, for those that have them, is it useful for obtaining part numbers? Specifically I'm looking for rear axle seals, gaskets, etc. The axle on mine is a GM corporate 15000 lb. single speed and in need of pinion seal and gasket numbers. Napa and the local Chevrolet parts don't have a listing but I'm hoping to get a seal number from the current one when I get it apart. Other than measuring I.D., O.D., and depth are there any options for finding a part number?
Last edited by Peggy M; 07/08/2024 5:49 PM. Reason: added more info to the title
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Mar 2004 Posts: 6,236 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,236 | You need a Chevrolet Heavy Duty Truck Parts Book. Do a search on the big auction site...you want one that covers up to 1960 or 61ish to make sure it covers any late year/next year upgrades. I've recently seen the 1955-2 thru 1960 2 ton and 2-1/2 ton...this would be a great addition to your truck library. Mike B  | | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | Thanks Mike, I'll keep an eye out for one. In the mean time I'll have to unload some hay from it and prepare to get greasy, 60 year old gear lube is not my favorite automotive fluid.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Nov 2005 Posts: 6,101 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,101 | Hy 78buckshot, I think the pinion seal for your truck is GM part number 3653618, that crosses to Napa part number NOS 25970 $26.49. dimensions of seal are I.D. 2.598 O.D. 3.486 Width 0.438, hope that helps. | | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | Thank you 3B, Napa on line shows that to work for a 1 ton, I don't know if it's the same seal for the big bolts but I'll keep the numbers handy.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | I pulled the yoke and bearing/seal retainer today, 3B is correct, GM seal #3653618 still in the retainer. Thank you gentlemen.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | I ordered the seal, felt packing, and speedi-sleeve stainless repair sleeve from my local CARQUEST/Advance store, should be available tomorrow.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | I put the rear end back together with the new seal, felt and yoke repair sleeve, I then cut new gaskets for the seal/bearing retainer and the rear inspection cover, a couple of gallons of gear lube and I hope she's leak free now.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Nov 2005 Posts: 6,101 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,101 | Hy 78buckshot, thanks for the report, glad to read it. | | | | | Joined: Feb 2016 Posts: 1,996 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,996 | Thank you for your input, when the numbers matched with what you came up with it reduced my apprehension to order the parts.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
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