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northerngmc · 03-14-2011, 11:32 AM

Has anyone here swaped the ring gear and pinion from 3.90 to 3.38 in the original rear end?

Just wonder how complicated the swap is?

And also wondering how well my original 235 will go with the 3.38 rear gear.

Hoping to get better highway speed out of my 59 GMC with the original 235.

Here is the link to the parts I am looking at.
http://www.tomsdifferentials.com/catalog.asp?pg=15

03-14-2011, 11:32 AM	#1
northerngmc Registered User Join Date: Jan 2004 Location: Whitehorse YK Canada Posts: 2,651	Rear gear swap 3.90 to 3.38 Has anyone here swaped the ring gear and pinion from 3.90 to 3.38 in the original rear end? Just wonder how complicated the swap is? And also wondering how well my original 235 will go with the 3.38 rear gear. Hoping to get better highway speed out of my 59 GMC with the original 235. Here is the link to the parts I am looking at. http://www.tomsdifferentials.com/catalog.asp?pg=15 __________________ Blaine 59 GMC 9314 a.k.a. Whoopee 68 C20 50th Anniversary a.k.a. The Rat http://www.flickr.com/photos/northerngmc/ http://www.members.tripod.com/P-wee/index_032.htm 1.61803 is one H of a lot better than 3.14159, no really it is!