How hard would it be to change a '79 f150 with a 351M from an automatic (c6) to a 4 speed od toploader? I changed a 71 4x4 from a stick to a C6 that was harder to find parts for but it was a weekender, by the way the 79 is a local drag truck and per rules it has to be a stick. thanks

 

if i understand, you are going to use this truck to drag race? if you are, you will scatter the o d toploader all over the track. those trannys had a weak cluster gear setup in them. they were bad enough with a little bit of hot rodding, i dont htink one would hold up in a racer of any sort. if you are going to race, i think the tremec is the tranny you want. that is the 5 speed used in the later model mustangs.

 

The T56? They are sticking those behind the 390HP 4.6L DOHC Cobra Mustangs. The rules state that I cant be a BB so I am using the 351M. I know the 400 is a SB but the judges say it is too big. Up here we have a pretty good yards so I will see if I can find a Tremec, I dont have any experience with them but I guess I will learn quick. I was beating the c****** and m***** just fine until they changed the rules for next season. I am confident about the 351M and I thought the toploaders were good trannys. I had a Warner T19 in my '71 that was a regular stump puller and I never had any problems with it in 250,000 miles. My rear diff. is a Dana 60 with 2.75 posi gears.

 

How did you get a Dana 60 with 2.75 gears?

 

Reference to irench's information removed by Moderator.

And secondly Torque1st you can have any gear ratio that you want with any rear end for about $250 if you supply the rear end, so my Dana 60 2.75 was never made by the factory but it was put on several trucks (the Dana 60) and I just had a custom set of gears made with the posi lock spindle put in. I am still wondering if anybody has done this transfer from an auto to a manual. I went and got my toploader three speed today and my new toploader 4 speed OD will be here tomorrow, its a complicated situation, I bought the three speed for $75 that had just be completely rebuilt but the guy didnt want to pay for it so I ended up with it after some good haggling and trading an old C6 with a cracked bellhousing. A few days later I found a new 4 speed toploader that had been recently replaced an old worn out one, and run for about 2,500 miles before the guy whacked an Elk and completely demolished his truck, in case you don't know a good sized Elk weighs in at about 800 pounds. I saw the truck and I almost cried, it was sad, to tell you the truth I am surprised that he walked away, anyways I took the 400 and the transfer case for $200, then I raced home. The transfer case went in my '71. The 400 went on the stand to be rebuilt and the toploader (3 speed) is on my heated garage floor (I didn't want it to get cold). But right next to it is a spot for the 4 speed OD. I think I will replace the old three speed in my '71, it's gettin awful tired I am going to put it to bed. Thanks for reading my post!

 

Thanks for that info man. I have a Dana 61 with a 3.07 ratio. Do you have a company name or a link for these custom conversions?

I will fix irench's post.

I am swapping my T-18 out to a guy with a C6. My knee won't take the clutch around town anymore. He has a Broco 4x4 and he will have to find the adaptor for the T-18 to his transfer case. I have the tailshaft and housing I need for the C6.

 

I have a friend here in town that is a CNC specialist and he made me the custom gears, his company is Lewis CNC, I don't have the number right off hand, and he can only do it if he has free time, I waited six months. But he made me 8 different ratios in about eight hours, It takes awhile to set up the machinery and program the computer, I had to buy 15 blanks because he cannot guarantee that they will all turn out especially the lower ratios from about 7.00 on.(by the way you waould not believe the torque those things put on the ground, good for real 4x4 terrain). Ithink you can buy a different gear ratio from summit. 14 of the 15 turned out so I only lost the cost of a single blank (about $65). Dave isn't set up to handle a single job you would have to buy at least 10 before he could consider it. I have nine trucks so I had a place to put them, you also have to supply the housing because there is a difference from the dana series and even from housing to housing , Dave will measure for each one and make a custom perfectly matched gears. thanks

 

I did this in a 68 basically you need a parts truck

1) need te peedals (clutch and brake) maybe the hangers too
2) the linkage
3) the drive shaft
4) the center piece (of your cab or cut with a torch)
5) the flywheel clutch throwout bearing bellhousing
6) and all the mounts and crossmembers (to be safe)
7) the last and most inportant the ability not to lose your temper

mine was a pain to put in I even had a heated garage with a lift I left my auto colum in
hope this helps

 

I will remember number 7. thanks!