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| | | | Joined: Aug 2015 Posts: 19 New Guy | | New Guy Joined: Aug 2015 Posts: 19 | First off I'm a new member, just purchased a 1951 3100, and have my first question. The rear seal on my transmission is leaking at the yoke input, and I'd like to ID my transmission so the correct seal can be purchased. It's a 3sp manual, iron case, open shaft. A quick check on another website shows it matching to a Saginaw (7 bolt cover, reverse on the case not tail housing). The numbers are as follows:
Drivers side case : GM3 3858992 (2 is badly worn)
186
Pass side case : GM1 3858998
C116
Pass tail housing : GM14
Photos can be provided if necessary. The trans may or may not be original. The truck has been modified in other areas. I just need to ID the make and model of the trans so the correct part can be purchased. I don't really need to know about ratios, etc. at this point. Maybe all tail shaft seals are the same (doubtful)?
Thank you in advance. I look forward to expanding my knowledge through this website! | | | | | Joined: Dec 2006 Posts: 206 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 206 | Its not original, Its a Saginaw 3 speed from ye mid 60's
Seals should be the same, measure your slip yoke diameter and compare | | | | | Joined: Aug 2015 Posts: 19 New Guy | | New Guy Joined: Aug 2015 Posts: 19 | Dave, thanks for the quick reply. Was definitely going to measure the yoke and inner tail housing, just looking for a starting point. Are you thinking this transmission has the same seal as the original transmission? I'm hoping to get the old one out without damaging it too much, which will make comparing a lot easier.
Thanks again! | | | | | Joined: Mar 2010 Posts: 10,299 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,299 | Take the seal out and take it with you to the auto parts store.
Ask them for a 1966 1/2 ton rear manual transmission seal.
I will bet a dollar to a donut (one to one odds these days) that it will match your old seal.
Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Aug 2015 Posts: 19 New Guy | | New Guy Joined: Aug 2015 Posts: 19 | Carl, perfect. I'll take that info and measurements with me.
Also, I'm assuming 80-90 gl4 gear oil is what I should use?
Thanks again for all the information. | | | | | Joined: Aug 2015 Posts: 19 New Guy | | New Guy Joined: Aug 2015 Posts: 19 | I found a replacement seal, the old had p/n 15041, so was able to replace it with the same. Also found some 85-90 gl 4 gear oil that is formulated for transmissions with bronze components. Changed both the trans and rearend and just having fun driving it now.
Thanks again for all the feedback, and I'll check back when I have another question. | | |
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