Once again I'm asking for help. Trying to choose a 3speed behind a 270 gmc. Saginaw 3spd and 4 speed. 4 speed has a missing gear tooth..how much of a concern is it.. I just want the truck drivable around the neighborhood not doing racing or pulling or anything till the budget allows it.
I wouldn't worry about a single missing synchro tooth much. I would worry more about where it went. Check all the main teeth for damage, poke around with a magnet, flush the case out before putting it to use.
Great thanks... I'll be asking a bunch of stupid questions if yall don't mind me asking them. I.e how to properly stab the cover and how to re attach the shifter arms.. Thanks in advance
The things that would give me pause are: Where are the missing pieces of the dog tooth? There appears to be damage to the tooth above the missing one and to the second tooth below it There is pitting on the lower gear tooth in the second picture. You've got an in line 6, which typically have a wide torque band, so the 3 speed would not be a particular detriment for the type of use you are proposing..
Not to support your choice in a Saginaw but in case you ask about what oil to refill the transmission with, use GL-4 grade, this grade is not in stock everywhere but I got Sta-Lube for my Muncie from NAPA, they had it in their local warehouse here.
You're not going to be abusing it, so run it. The synchro hub slides over all those teeth, including the broken teeth, so the drive is spread over all the teeth around the whole circumfrence of that unit..
Good point. What's found in most auto parts store is not manual transmission lube, but differential lube. That's GL-5, and it eats brass.
The busted piece is likely suspended in oil in the bottom of the case, no worries... considering what I have found in transmissions and oil pans over the decades.
Back in high school my pal and I both had 57 Chevys, both of us blew up the rearends in them, he did it twice though as he didn't reach down into the glop in the bottom of the housing and retrieve the broken bits.
I was going to ask,thanks. Good to know thanks. Thank you. Thanks..I did find all the bits stuck to the magnet. I did find the broken piece Thanks It's just to move it around the yard..if it fails,I got a Muncie or I will look for a different trans.. I just can't wait around till everything is perfect..gotta move fwd
Personally, I never consider a question to be a "stupid question" if someone is genuinely trying to learn something that they don't know. Ask all the questions you want,...........but you may get some stupid answers sometimes. Generally we all try to help when we can, or also learn something if we didn't know the answer either.
As far as lube requirements, for light-duty use you could probably fill it with 30w motor oil or any generic straight weight gear lube, couldn't you? The problem with using GL5 or newer synthetic gear lubes is that they can "over lubricate" the brass blocker rings and make them ineffective and difficult to shift. The newer synthetic lubes are formulated to work with the later style blocker rings that are faced with an organic clutch material, like the facing on automatic transmission clutch plates and bands.
Magnetic drain plug and as a note drag racers used to cut every other tooth off for better/quicker shifts; they lasted longer than one would think. You are good.
"Overlubricating" not a thing. The additive package in GL-5 has so much Sulphur and sulfated compounds in it that it literally erodes brass. It will eat synchronizers over time alone. Heat and pressure make that even worse. 30W does not belong in an manual transmission that is not being operated in sub-zero temperatures.
No, but 90wt. will keep a 5 cyl., V8, 56 Dodge on the road for a couple of more days. You can also substitute water for brake fluid when you pinch off the line to a blown wheel cylinder while in some small German village.
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