ITT: We discuss T5 swaps and other information.
#1
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Well I finally bought one. 110k on it from an 02 mustang. Paid $300 for it in oregon, your prices may vary.
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I'm going to start out with some information I have gathered from around the web. Mostly from Savington's thread.
Why I chose what I chose:
I picked a 99-04 box for a couple reasons, the main one being strength. It has the stronger gears of the V8 box, with a .68 overdrive. This is a little low, but I'm hoping it will be manageable. It has an electronic speedo sender, which can be used to connect to a megasquirt and an NB cluster. It was also cheaper than the 90-93 boxes that are more popular.
I'm going to swap in an input shaft from a 90-93 box, which will give me the same dimensions of the Astro A-5's which can handle 485+ ft/lbs.
Plans for the swap:
I'm going a similar route as Savington. I will chop off a spare miata bellhousing. Build a 1/2" flange that matches the t5. weld the miata bellhousing to the t5 flange. Get some clutch discs for the twin disc that fit the mustange input shaft. Aquire correct pilot bearing and make some sort of throwout bearing work. Use stock miata hydraulics.
Some sort of PPF adapter.
Plan for the shifter: Pop out freeze plug. Build extension rod that connects to the shifter inside the box. Keeps the dentents in the box. Send a shaft out the freeze plug with a bushing and an oil seal to keep the oil in. Mount a shifter back behind where the miata shifter goes. Hope it doesn't interfere with the driveshaft.
Somewhere along the way I will screw up horribly and fail, but at least it will be documented!!!
Post questions and information here!
Parts and other information: https://docs.google.com/spreadsheets...it?usp=sharing
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I'm going to start out with some information I have gathered from around the web. Mostly from Savington's thread.
A quick change of direction, and a peek into the future. One of the many things we'll use this chassis to develop is a T5 swap kit, and this is the beginning of that development. The box is a -238 code from a 1996 3.8L Mustang, which is desirable for a few reasons:
For people who want a 100% bolt-in solution, you'll have to shell out $1100 for a new T5z box, but converting the V6 box to V8 spec is easy. You need the input shaft, bearing, bearing cover plate, and a shim kit, all of which can be had for ~$140 or so, which means you can put the gearbox itself together for well under $300 without any special one-time deals or hard to find parts.
The clutch disc was $110 and it's a performance organic disc with a 10-spline T5 center. It will get swapped for a 26-spline piece when I do a G-Force gearset next year. All the G-Force boxes are set up around 7.18" input shafts (V8), not the ~7.8" shafts that came in the V6s, so in order to accomodate built gearboxes, we'll build around the 7.18" length.
The bellhousing is cut off a blown 5-speed (everyone considering this swap probably has a blown 5-speed in their garage) and it will be milled down to the correct length and welded to an adapter plate which will be done in a few weeks. Using a chopped-up OEM bellhousing means I can retain the stock TOB, stock clutch fork, and stock hydraulics, so from the front, it will look like a Miata transmission with a 10-spline input shaft sticking through, and there are no issues with reliability or fitment on any of those critical items.
So that's the trans>engine attachment all sorted out. Next big puzzle is the shifter extension. The PPF bracket should be a little easier.
![](https://i.imgur.com/hjAfbNY.jpg?)
- It's a World-Class box
- It has a 3.35 1st gear which means that you can swap the input shaft from a 3.35 V8 box into it with ease.
- The 0.75 overdrive is a big step down from the .843 in the car now, but not as deep as the .63 ODs in all the V8 boxes
- It has an electronic speedo sender, and with a Dakota box and a little work, it should talk nicely to the NB speedometer and MS3
- It was $130 at the junkyard, not $800 like all the V8 boxes are
For people who want a 100% bolt-in solution, you'll have to shell out $1100 for a new T5z box, but converting the V6 box to V8 spec is easy. You need the input shaft, bearing, bearing cover plate, and a shim kit, all of which can be had for ~$140 or so, which means you can put the gearbox itself together for well under $300 without any special one-time deals or hard to find parts.
The clutch disc was $110 and it's a performance organic disc with a 10-spline T5 center. It will get swapped for a 26-spline piece when I do a G-Force gearset next year. All the G-Force boxes are set up around 7.18" input shafts (V8), not the ~7.8" shafts that came in the V6s, so in order to accomodate built gearboxes, we'll build around the 7.18" length.
The bellhousing is cut off a blown 5-speed (everyone considering this swap probably has a blown 5-speed in their garage) and it will be milled down to the correct length and welded to an adapter plate which will be done in a few weeks. Using a chopped-up OEM bellhousing means I can retain the stock TOB, stock clutch fork, and stock hydraulics, so from the front, it will look like a Miata transmission with a 10-spline input shaft sticking through, and there are no issues with reliability or fitment on any of those critical items.
So that's the trans>engine attachment all sorted out. Next big puzzle is the shifter extension. The PPF bracket should be a little easier.
![](https://i.imgur.com/hjAfbNY.jpg?)
Necro post. My research shows that the 94-98 boxes were from the 6-232, and the 99-04 were from the 6-238. And thats when the electronic speedo switchover happened. Am I totally off base?
Correct me if I'm wrong.
90-93 V8 box = correct length input shaft, bad overdrive. More $$$ because mustangs like em.
94-98 V6 box = Longer input shaft. But good overdrive. Uses 3.35 first gear so we can use a v8 input shaft. Mechanical speedo
99-04 V6 box = Longer input shaft. Good overdrive. 3.35 first gear, but with electronic speedo.
94-95 V8 box = Longer input shaft, bad overdrive, 3.35 first gear
Correct me if I'm wrong.
90-93 V8 box = correct length input shaft, bad overdrive. More $$$ because mustangs like em.
94-98 V6 box = Longer input shaft. But good overdrive. Uses 3.35 first gear so we can use a v8 input shaft. Mechanical speedo
99-04 V6 box = Longer input shaft. Good overdrive. 3.35 first gear, but with electronic speedo.
94-95 V8 box = Longer input shaft, bad overdrive, 3.35 first gear
232 is a GM box. 238 is the 95-97 V6 Ford box.
Identification Key to Borg-Warner T5 transmission ID Tags
Ford World Class Transmisson identification
Identification Key to Borg-Warner T5 transmission ID Tags
Ford World Class Transmisson identification
Wow there is all sorts of conflicting information out there.
Going to edit this post instead of continuing to fill up your thread.
Auto/Man Trans Gear Ratios for V6 & GT ? - The Mustang Source - Ford Mustang Forums
But then according to this: http://www.mongosgarage.com/tech/t5/T5Numbers.PDF the 98-99 had a .73 overdrive. and the 99-01 doesnt have ratios listed.
I guess unless I can find some real info the 94-98 is the safe one to go with. And I guess the 96-98 had the electronic speedo?
I wish other platforms had a version of mt.net, with actual fact checking instead of just numbers.
Going to edit this post instead of continuing to fill up your thread.
Auto/Man Trans Gear Ratios for V6 & GT ? - The Mustang Source - Ford Mustang Forums
But then according to this: http://www.mongosgarage.com/tech/t5/T5Numbers.PDF the 98-99 had a .73 overdrive. and the 99-01 doesnt have ratios listed.
I guess unless I can find some real info the 94-98 is the safe one to go with. And I guess the 96-98 had the electronic speedo?
I wish other platforms had a version of mt.net, with actual fact checking instead of just numbers.
I picked a 99-04 box for a couple reasons, the main one being strength. It has the stronger gears of the V8 box, with a .68 overdrive. This is a little low, but I'm hoping it will be manageable. It has an electronic speedo sender, which can be used to connect to a megasquirt and an NB cluster. It was also cheaper than the 90-93 boxes that are more popular.
I'm going to swap in an input shaft from a 90-93 box, which will give me the same dimensions of the Astro A-5's which can handle 485+ ft/lbs.
Plans for the swap:
I'm going a similar route as Savington. I will chop off a spare miata bellhousing. Build a 1/2" flange that matches the t5. weld the miata bellhousing to the t5 flange. Get some clutch discs for the twin disc that fit the mustange input shaft. Aquire correct pilot bearing and make some sort of throwout bearing work. Use stock miata hydraulics.
Some sort of PPF adapter.
Plan for the shifter: Pop out freeze plug. Build extension rod that connects to the shifter inside the box. Keeps the dentents in the box. Send a shaft out the freeze plug with a bushing and an oil seal to keep the oil in. Mount a shifter back behind where the miata shifter goes. Hope it doesn't interfere with the driveshaft.
Somewhere along the way I will screw up horribly and fail, but at least it will be documented!!!
Post questions and information here!
Parts and other information: https://docs.google.com/spreadsheets...it?usp=sharing
Last edited by aidandj; 09-15-2016 at 09:48 PM.
#2
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I am in for results. I was discussing this swap with a well known miata fabricator because I wanted him to use my car as the guinea pig for a kit he could offer to the community. He ended up deciding that his other projects had a bigger market and were easier for him to deliver in a way that he could sell so he chose not to pursue. Very disappoint.
#4
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Nope. Andrew is working on a kit for people who would like to pay.
This thread is for my personal transmission swap, and for information for others to use along their way.
My next research step is going to be pilot bearing. I'll measure a stock bearing tonight and the input shaft of the t5 and start searching.
This thread is for my personal transmission swap, and for information for others to use along their way.
My next research step is going to be pilot bearing. I'll measure a stock bearing tonight and the input shaft of the t5 and start searching.
#11
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Pilot bearing:
Mustang:
Time to do some searching and find what we need.
Mustang:
- ID: 0.6721
- OD: 1.487
- Width: 0.732
- Type: Needle
- ID: 0.590
- OD: 1.378
- Width: 0.4331
- Type: Ball
- ID: 0.6721
- OD: 1.378
- Width: 0.4331
- Type: Ball
Time to do some searching and find what we need.
#12
SADFab Destructive Testing Engineer
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Nobody has done the shift extension the way I plan, AFAIK. The video on youtube is a bit different. Idk exactly where it was though.
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Or just cut a big hole. I have 3 spare 5 speeds right now.
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Just what i came up with quickly on mcmaster. its only 0.394" wide but would work. Ill dig in the timken catalog tomorrow
McMaster-Carr
17x35x11mm is what were after for those that measure in proper units
McMaster-Carr
17x35x11mm is what were after for those that measure in proper units
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But then again, I'm not sure how accurate it needs to be. T5z input shaft was .017" off SBF crank centerline when the bellhousing dowels were aligned.