Thinking out loud here

[willowbilly3]

Steve, there is more about T5s than you want to know or have room inside your head for. Flat Earnie has piled up a lot of good links.

http://www.jalopyjournal.com/forum/show ... p?t=169265

You are basically sorta correct but changing the input means tearing it all the way down. Don't overlook the Ford 4 banger ones, they have better ratios and should hold up to sesable driving behind a stout 240. The junkyards here can't sell those and $75 will get you your choice.

[willowbilly3]

Depending on what you are shooting for, I would keep an eye open for the later pickup 5 speed as the small block bolt pattern is the same. You would need to do a juice clutch. Another option is the 4 speed with 4th over drive. They are several versions and one version has a top shifter. Also there was the one that looks like a toploader car tranny and had the outside shifter, then the lesser SROD styles.

[dablack00]

I don't think I would use the mazda built five speed, I think I would go w/ a 4 cyl T5 or a V8 T5. It really depends on what rear gears you have? If you have 3.7s or deeper (numerically higher), then I would do the V8 T5 for the .67 OD. If you have some 3.0 in your truck then I would go w/ the 4 cyl T5 for the deeper 1st gear and the .80 OD.

Around here you can pick up a 4 cyl T5 in good shape for $50. bad shoe productions sells a rebuild video for $40 (or so) and you can get a rebuild kit for $250. So, you can be into a good T5 for around $350. Or you can get one off ebay already rebuilt for $500-650 ish.

[willowbilly3]

I don't think I would use the mazda built five speed, I think I would go w/ a 4 cyl T5 or a V8 T5. It really depends on what rear gears you have? If you have 3.7s or deeper (numerically higher), then I would do the V8 T5 for the .67 OD. If you have some 3.0 in your truck then I would go w/ the 4 cyl T5 for the deeper 1st gear and the .80 OD.

Around here you can pick up a 4 cyl T5 in good shape for $50. bad shoe productions sells a rebuild video for $40 (or so) and you can get a rebuild kit for $250. So, you can be into a good T5 for around $350. Or you can get one off ebay already rebuilt for $500-650 ish.

Dustin says the Mazda tranny is fine and puts them behind 4BT

[dablack00]

Dustin is right. They are fine, but I like to do everything myself and I haven't seen a video on how to rebuild them, plus they are a little harder to find and rebuild. T5s are everywhere, have lots of support, and have multiple gear ratios to choose from.

My vote is T5.......but the mazda one will work too.

[spartman]

Right now the truck has 3.70's in it.

I also have a set of 3.25's though too.

My goal with the od would be to cruise about 2000 to 2500 rpm at 60-65.

[dablack00]

What is your tire height? I can calculate your RPMs in overdrive at any speed. Just let me know.

[averagef250]

The Mazda's are simpler than a T-5 to tear down and get back together. For the mazdas you will need a 20" or longer jaw two jaw puller and while you can get the mainshaft nut off with a pipe wrench it's best to buy the right size socket and cut it and weld a 12" or so piece of pipe in to make a super deep socket so you can use an impact and torque wrench with it.

With the mazda you'd definitely want the 3.25's though. They have a real deep 1st and 5th is only .8.

[spartman]

Dablack thanks for the offer but I have an excel spreadsheet with the formulas in it already.

right now I can get a T-5 for about 50 bux fairly easily, not so sure on the mazda transmission.

Looking at one on ebay that would cost about 130 total so far, and that would be with shipping.

[MadMaxetc]

Check out my writeup on my website.

I did a Mustang T-5 behind my 300.

I Love IT!! 15/20mpg...with a 4bbl!