Solex 27 #1 Posted August 4, 2015 I have a 1986 308-8 that was upgraded with a magnum 12 engine. I read somewhere that the 312-8 came from the factory with a different transmission with larger 1/1/8 axels compared to the 308-8 smaller 1 inch units. Comparing the two drawings the transmission assembly calls for a 5961 axel. The 312-8 drawing mentions this part number as well as a 105875. Is this part the larger axel?In addition I was told the 312-8 has different gearing? Share this post Link to post Share on other sites
bmsgaffer 2,045 #2 Posted August 4, 2015 I believe gearing hasn't changed since 1960, and depending on the year the 312 may have had the 1in axles too. Its not true in all cases but i think the 300 series were mostly 1" axles and the 400 and up series favored the 1 1/8"But (and here's the kicker) if the transmission is working fine, dont switch it. Even the "light duty" axles and differential can handle quite a bit of abuse as evident of the many people on here doing heavy duty work with them. You will probably only consistently run into problems if you over weight it, run an FEL, or are doing pulling. 4 Share this post Link to post Share on other sites
can whlvr 993 #3 Posted August 5, 2015 I have a 308,and ive put her through heck and back,plowed for 25 years,pulled trees and rocks,anything my bigger tractors can do,these trannys are very strong and even the lighter 4 pinion 1 inch are formatable Share this post Link to post Share on other sites
