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SM465 top cover install

Jake_C_

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For anyone wanting some more information on how to remove and re-install a SM465 top cover. I just got done doing it myself and I thought I would offer up some pointers. When you go to take the cover off, it has to first be halfway in reverse, I recommend taking the shifter out at this point while leaving it halfway in reverse but it’s not necessary. there are two studs on the top cover that fit into two holes on the body of the transmission, lift up the cover a little to clear the studs and move it to the left (assuming you’re facing the same direction as the input shaft). Lift up on it and wiggle it and eventually it should come off, just keep messing with it. Once you get it off you can look inside and see three forks:
450F6D22-411D-407D-902F-D8944021CCC2.jpeg
These three forks fit into three grooved metal wheels in the transmission:
9A2A2899-6719-44E5-9B4A-B325EC65796C.jpeg
the one for the reverse gear is far down and hard to see, here’s a close up picture:
3712E786-960D-4D13-A062-36EA28B07CB3.jpeg
also notice the reverse gear is halfway engaged with the gear above it, this is what it should look like when you have your shifter halfway in reverse. If your gear isn’t halfway engaged you can slide it into place by hand. Put your shifter back in the top cover and make sure it’s still halfway in reverse. The two other forks will be in neutral. When you’re putting it back on, the forks should line up with the grooved wheels and you can make sure it lines up as you put it on, when I put mine on it kind of settled to the left, once it was all the way down I pushed it to the right and it fell the rest of the way into place. Put a couple bolts in the top cover and put the shifter in to make sure it shifts into all gears and the input shaft spins as it should in all gears. If everything works fine then you’re done. I hope this helped someone out, I didn’t find much information online when putting mine back on so maybe this will be useful for someone.
 

imiceman44

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For anyone wanting some more information on how to remove and re-install a SM465 top cover. I just got done doing it myself and I thought I would offer up some pointers. When you go to take the cover off, it has to first be halfway in reverse, I recommend taking the shifter out at this point while leaving it halfway in reverse but it’s not necessary. there are two studs on the top cover that fit into two holes on the body of the transmission, lift up the cover a little to clear the studs and move it to the left (assuming you’re facing the same direction as the input shaft). Lift up on it and wiggle it and eventually it should come off, just keep messing with it. Once you get it off you can look inside and see three forks:
View attachment 326481
These three forks fit into three grooved metal wheels in the transmission:
View attachment 326479
the one for the reverse gear is far down and hard to see, here’s a close up picture:
View attachment 326480
also notice the reverse gear is halfway engaged with the gear above it, this is what it should look like when you have your shifter halfway in reverse. If your gear isn’t halfway engaged you can slide it into place by hand. Put your shifter back in the top cover and make sure it’s still halfway in reverse. The two other forks will be in neutral. When you’re putting it back on, the forks should line up with the grooved wheels and you can make sure it lines up as you put it on, when I put mine on it kind of settled to the left, once it was all the way down I pushed it to the right and it fell the rest of the way into place. Put a couple bolts in the top cover and put the shifter in to make sure it shifts into all gears and the input shaft spins as it should in all gears. If everything works fine then you’re done. I hope this helped someone out, I didn’t find much information online when putting mine back on so maybe this will be useful for someone.
I had to learn this the hard way, I ended up talking to a mechanic friend who told me all that.
By the way there was a thread on this a few weeks ago.
 

diesel4me

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One day my friend had a C30 pickup on his lift when I showed up,and was cursing,he was using the "squirt bottle" to refill the gear oil in the transmission after he installed a new clutch,and the owner wanted new gear lube ,because he had to drive it with the clutch failing,and "ground the gears" some..

Gear lube was drooling everywhere and about half the bottle's worth may have actually made it to the transmission thru the filler plug..
I asked him "Why didn't you just dump it in the top "?...
He looked at me and said "I never thought of that"!.:blush:...:doah:.the shifter was still out and lying on the floor of the truck...

I had done the same thing after I swapped a SM465 into my '72 K5..took me like half an hour to get 2 quarts to get into the transmission,and half of it poured back on ME!..then I realized I could just dump it in thru the shift lever hole!..
 

imiceman44

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One day my friend had a C30 pickup on his lift when I showed up,and was cursing,he was using the "squirt bottle" to refill the gear oil in the transmission after he installed a new clutch,and the owner wanted new gear lube ,because he had to drive it with the clutch failing,and "ground the gears" some..

Gear lube was drooling everywhere and about half the bottle's worth may have actually made it to the transmission thru the filler plug..
I asked him "Why didn't you just dump it in the top "?...
He looked at me and said "I never thought of that"!.:blush:...:doah:.the shifter was still out and lying on the floor of the truck...

I had done the same thing after I swapped a SM465 into my '72 K5..took me like half an hour to get 2 quarts to get into the transmission,and half of it poured back on ME!..then I realized I could just dump it in thru the shift lever hole!..
Done that all the time.
 
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