What size bolt?

[jdiesel33]

Attaches a 727 tranny to a 440 block? Width and length?

thanks

[John_Kunkel]

The top four bolts are 3/8"-16 X 1 1/4" long.


The bottom two bolts are 7/16"-14, the starter side is 2" long and the opposite side is 1 3/4" long.

[jdiesel33]

thanks man. i appreciate it.

[jdiesel33]

Ok, I need help on this. I am going to pull the engine and put it on an engine stand, standard kind with the 4 adjustable arms that bolt to the block. As I understand it, I need to go and buy 4 bolts before hand to mount the engine to the stand. A previous post on this thread gave me the length and width of the bolts that go from the tranny to the block, but I guess that isnt enough. I need thread pitch and width also right? I am taking the engine and tranny out all together. Should I just wait till I get it out and pull those bolts then just get longer versions of those? Would I just take the length of the bolt tunnels on the engine stand and add that to the length of these bolts or do they need to be even longer?

Thanks

[John_Kunkel]

Measure the length of the arms and add 5/8"-3/4", the thread for all four is 3/8"-16 since normally only the upper bolt holes are used for mounting to the adjustable arms.

[jdiesel33]

So that is all I need to know? My friend told me I needed more info about the threads themselves like pitch and width? No?

[jdiesel33]

I assume I can just get these at a Home Depot or Lowes or something? I would assume I would need some pretty good quality ones.

[70redbee]

I would get a grade 8 bolt just to be sure in the size you need. Never can be too cautious when it comes to your prized mopars.

[John_Kunkel]

So that is all I need to know? My friend told me I needed more info about the threads themselves like pitch and width? No?

3/8"-16 is the diameter and the thread pitch.

[jdiesel33]

good enough. i guess i didnt know exactly what that notation meant. i probably didnt communicate it correctly. thanks for all the help.

[jdiesel33]

Just want to make sure Grade 8 is sufficient on this. The guy at Home Depot said I should go with a grade 10 or above. Is grade 8 sufficient? O'Reilly's and Napa both top out at 8.

[jdiesel33]

Also, found a few articles such as this one saying to use Grade 5 bolts!!!!! What is the right one? I hoped to buy some tonight. Any help would be appreciated.

"I recommend AGAINST grade 8 for reasons already mentioned. Grade 8 is superior in items of tensile strength; that is to say where the force is parallel to the length of the bolt. U joints, headers, axle brackets, wheel studs, etc. Grade 5 has a slightly lower tensile strength but its much more malleable. Grade 8s don't bend, they break. Grade 5s will bend and thats a good thing since most of your weight on an engine stand is shear weight... and the tensile strength of grade 5 is waaaay more than sufficient on an engine stand.

I used to think that more is better, but when it comes almost everything in the automotive world, RIGHT is better. Everything has its application, and hard brittle bolts like grade 8 have broken on me before in engine stands and engine lifting.

If you don't believe me, try lifting an engine with a long grade 8 bolt. It will break. But, if you have a shorter grade 8 bolt that you can torque down against the chain, it has a chance because its under tensile pressure and it gets shear strength from the fact that its wedged against the block and can't move. Now do the same test with a grade 5 and the long bolt will just bend.

That was my long winded way of saying; use grade 5 and you'll be happy. Use grade 8 and they'll probably last forever, but if you drop a box out of the rafters on the engine a grade 8 might snap, but a grade 5 will just deform. Ask me how I know. I had two grade 5s and two grade 8s in my Caddy 500 on the stand. The box of toys I dropped from the rafters sheared the grade 8s leaving the engine to hang on the mangled grade 5s."

[John_Kunkel]

I've been using Grade 5 bolts on all on my engine stands for 40 years, never had a failure.

People tend to go overboard on hardware just because it's available, each of the bolts holding a 440 to an engine stand is only holding about 150 pounds.

[grdprx]

Appreciate this thread, comes along just when I need it!

So, I went to Lowes to get the propper sized bolts; they were out of the 1 1/2" 7/16 which I needed for the motor mount.  Didn't carry the 1 3/4..

Home Depot doesn't carry 7/ 16 bolts!  So, I'll have to go by O'rileys or something..

[maxwellwedge]

Motor mount bolts are fine thread - for a reason.
Just call Frank Badalson (and others) they have all the correct hardware for all this stuff for a measly few bucks more and no worrying.