T-20 shift pin Rockwell hardness test

[brushcutter]

I started to name this "The Long Ago Promised T-20 Shift Pin Rockwell Hardness Test", but I was concerned that I would not have enough space - for obvious reasons. Long ago I said that I would test the Hardness of the shift pins but due to some now forgotten reason...I forgot about it. Everybody say THANK YOU to Racerone3 for jolting my memory kind of like this: HEY DUMBA** DID YOU EVER DO THAT HARDNESS TEST YOU PROMISED YOU WOULD DO? Just kiddin but he did very politely ask what my results were. So this morning I got up and as I drank my first cup I dragged my sorry self to the shop and yanked one of my shift pins and carried it to work, for the test.

The result : 62 rockwell.

The machinist I work with said "all you need to do is get some 1/4" case hardened dowels and you are in buisiness." A similar test on a grade 8 bolt gave an average result of 34 rockwell (way too soft)! You can buy them from MSC: I'm looking at my 2004-2005 MSC book and you could buy them by 100 pcs then for as low as $12.41 for 3/4" length. $12.16 for 5/8" length. So anyone who has one out (mine was stuck in the shifter) can let everybody know what length is needed.

I must say, as you can all see, anybody selling these for $8 each is making a killing!

Sorry this took so long to get done, and thanks again Racer for reminding me.

[racerone3]

thanks for checking into it! i just happen to have one of those $8 shift pins on my work bench. 0.742" looks like 3/4 to me. slightly beveled on both ends. you could chuck it lightly in a drill and lightly spin it against a belt sander to achieve the bevel if you didn't have a lathe.
do you have a MSC part # for the 3/4 pins? save someone (me) some time digging in that big book.

here are a few pics showing the length, and the bevel on the end of the pin

[brushcutter]

No problem. $8.00 What a crime!

In the MSC Industrial Supply book the part # is 06024079, but the book is several years old. This # is for 100 1/4" diameter X 3/4" long bright finish 0.0002 standard oversized Rockwell c 60 to c 64 dowel pins price: $12.41/100. I'm not sure if the part # will still be the same.

[LarryW]

MSC Google Search Results

It says grade 8 though? I guess better softer then to hard and where the collar out?
Thanks for taking the time to do the test!!!

[racerone3]

price is up to $17.41 for 100 of them. MSC Shopping Cart i'm going to get a box of them and make up some. i have 3 t-20's to rebuild this summer, and i only know for sure that one of the shift pins is good. if i need to replace 4 i'll still be $14 cheaper than buying actual shift pins

[brushcutter]

price is up to $17.41 for 100 of them. MSC Shopping Cart i'm going to get a box of them and make up some. i have 3 t-20's to rebuild this summer, and i only know for sure that one of the shift pins is good. if i need to replace 4 i'll still be $14 cheaper than buying actual shift pins

AND THE BEST PART IS, YOU'LL STILL HAVE ENOUGH TO REPLACE THE PINS IN 48 MORE T-20S, that's like... almost a lifetime supply! For $17.41 and shipping ....sweet

[racerone3]

here is my next question, does anyone have a T-20 torn down with the double o-ring plungers? if so, i need pics/ measurements on the position of the second o-ring in relation to the first. while i'm rebuilding all our tranys i'm going to have my machinist buddy cut some groves in the plungers i already have.

[Mike]

Hey racerone3, if you can't get some dimensions there are a few pictures of the double o-ring plungers in the T20 Rebuild Article on page 6 and a real good side shot on page 3. Maybe you can print a picture off and scale it off of that.

[racerone3]

good call Mike, i looked at those pictures the other day, but hadn't thought of measuring off the pics. they probably don't have to be perfect... i just want them in the same general area. my machinist on the other hand will want dimensions. worst come to worst, i'll shoot from the hip, make up some measurement and he'll be off and running