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Discussion Starter · #21 ·
The short length of the S197 Mustang T5 is the primary advantage over the GM version. This allows the driveshaft to be longer. Short driveshafts are difficult to balance and can make it more difficult to get acceptable u-joint operating angles.
 
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The short length of the S197 Mustang T5 is the primary advantage over the GM version. This allows the driveshaft to be longer. Short driveshafts are difficult to balance and can make it more difficult to get acceptable u-joint operating angles.
So, bigger is better with the shaft?
 

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T5 Transmission

The T5 is only in the V6 versions of the Mustang. The V8s came with a bigger and stronger transmission. In researching the Ford T5 the only weakness is the low first gear. If you change that out it will handle around 400lbs of torque. Since no Opel motor will get close to that the Ford T5 should be nearly indestructible in our application. If you put an electronic to manual speedometer converter on it, it will raise the price around 300+ bucks. But then now matter your tire size or rear end ratio you can always correct the reading to be pretty accurate.
 

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T5 Transmission

If using the Ford T5 will a 94 V6 GM bellhousing with a Ford bolt pattern work so that we could start with an Opel motor and then switch to a 3500 V6?
 

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Discussion Starter · #25 ·
If using the Ford T5 will a 94 V6 GM bellhousing with a Ford bolt pattern work so that we could start with an Opel motor and then switch to a 3500 V6?
I don't claim to know, but seems to me that the input shaft would probably have to be changed. Length, diameter of pilot bearing and number of splines would be the concerns. Also, input bearing and retainer. Did GM use the Ford bearing or the GM bearing on that model? Depth of bellhousing determines length of shaft, and don't forget you'd be going from 1-1/8" thick adapter plate to no adapter.
 

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I don't claim to know, but seems to me that the input shaft would probably have to be changed. Length, diameter of pilot bearing and number of splines would be the concerns. Also, input bearing and retainer. Did GM use the Ford bearing or the GM bearing on that model? Depth of bellhousing determines length of shaft, and don't forget you'd be going from 1-1/8" thick adapter plate to no adapter.
I'm with you.

It all depends on the specs of what you want to do with the project.
If you start with a Ford T5 with a GM bell housing, then get the adapter made for that transmission then it should be just as easy as removing the adapter and bolting the GM bell back on.

But starting with a FORD T5 with a FORD bell, then making the adapter, then trying to revert to a GM bell is going to be asking for problems.
 

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T5 Transmission

I'm with you.

It all depends on the specs of what you want to do with the project.
If you start with a Ford T5 with a GM bell housing, then get the adapter made for that transmission then it should be just as easy as removing the adapter and bolting the GM bell back on.

But starting with a FORD T5 with a FORD bell, then making the adapter, then trying to revert to a GM bell is going to be asking for problems.
Looking to start with the Opel adapter to mate the Opel bellhousing to the Ford 05 and newer T5. Then at a later date remove the adapter and bellhousing and substitute it with a 93 or 94 GM bellhousing with a ford pattern. That would allow me to keep the same transmission but switch engines.
 

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Looking to start with the Opel adapter to mate the Opel bellhousing to the Ford 05 and newer T5. Then at a later date remove the adapter and bellhousing and substitute it with a 93 or 94 GM bellhousing with a ford pattern. That would allow me to keep the same transmission but switch engines.
Then I'd suggest you start with a Ford T5 with a GM bell.
Just keep in mind that the only two T5 swaps have been Mustang or S10. Neither of which lines up with what you are thinking.
 

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Discussion Starter · #29 · (Edited)
I'd like to update some information I provided earlier about driveline angles. I've spent some more time fine tuning things over the last few months and have also corrected a rookie mistake I'd made. My error was a misunderstanding in the way the Spicer driveline angle calculator worked. It is often the case that when the pinion end of the differential is pointing up towards to motor, this is considered an up-slope. However, in the case of the Spicer calculator mentioned above, this would be a down-slope, which I eventually found buried somewhere on the Spicer web site. In other words, my calculations were off.

I also had recently changed my torque tube donut from the OGTS HD donut back to the stock hardness, and changed my rear suspension bushings from poly back to rubber. While vibration was not really a problem after these changes, I felt that the transmission down-tilt was excessive, I had too many spacers on the torque tube mounting bracket for my liking, and knew my angle calculations to be off due to my error.

SO... I undid my transmission crossmember and torque tube mounting bolts and started over. What I ended up with was this, all down-slopes (front higher than rear). These numbers supersede those provided in my post of 5/7/18. The site will not allow me to edit that previous post.

Transmission 4.4 degrees
Driveline 2.5 degrees
Rear Pinion (torque tube propeller shaft front yoke) .7 degrees

This results in a front U-joint operating angle of 1.9 degrees, and a rear u-joint angle of 1.8 degrees (see attachment). U joint operating angles should be no more than 3 degrees, and within 1 degree of each other, so we're good on both counts. A test drive confirmed no driveline vibrations up to 90 mph.

The good news is that it takes nothing special to get there. I have the transmission just about as high as it will go in the tunnel, which results in the 4.4 degree transmission down slope. We couldn't really go any higher without either shortening the T5's shift tower or enlarging the hole in the GT's tunnel. The latter would not be all that difficult, as at its upper limit the transmission only hits on the very right corners of the shift tower, but cutting into my Opel would be an absolute last resort for me and because the angles work as is, there is really no reason to go any higher. If I had the chance to make my adapter again though, I would have put a little less side-to-side tilt in it. You may remember that the engine in the GT is tilted to the right to allow the carb to fit under the hood. We tilted the adapter 4 degrees as well, but I think it should have been slightly less. Now the shifter sits in the hole just slightly off center, so first gear feels like it's is where third should be.

At the torque tube, the stock factory setup calls for one thick spacer under the two front mounting points. I added a couple more. This lowered the front of the pinion slightly to get the operating angles where they needed to be.

In short, shoot for around 4.5 degrees down tilt on the transmission and you should have no problem getting the U-Joint angles within spec by adding or removing spacers at the torque tube mounts.

I have probably 1,500-2,000 miles or so on the T5 now. It has really transformed the car in highway driving, and the e-Bay Mustang shifter I used (see earlier posts) has not caused me any issues.
 

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This is a very interesting swap and I think it will work great for Frankenmutt. I am flipping a coin between a built TH200 with high stall for a "clutch-less" 3 speed, or a manual swap for the stock 4 speed.

I just broke one of my 4 speeds last weekend, not sure what broke yet though but it's locked in first gear but still drives.

Anyway. I would be interested in the adapter if there was one floating around to have on a shelf, right now I am guessing that I will be heading towards a stronger and newer manual trans like this than a TH200 swap.

I have my spare 4 speed that was supposed to be ready to go in, but the tail shaft bushing seems to be too tight and won't let the drive shaft go in. We discovered the batch of synchro's were too tight when I got them from Gil, but never checked the rear bushing until last night.. too late to make this Sunday's race with it now.

As said, if anyone has an adapter they are willing to part with, or another batch will be made soon, I would like to get my hands on one. Or possibly the CAD file and I can have one machined here by the shop I use for other parts.

Ryan
 

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Okay, another question.

Is the front (shaft and mounting surface) of this 05-10 T5 the same as the early Fox body one? I found a retrofit tail shaft housing that works on the earlier T5 but moves the shifter forward like the S10 and has improved oiling and other features in the tail area, plus it keeps it a slip yoke instead of a flange which isn't a huge issue, just keeps the shaft a bit simpler and lighter.

I haven't found blue prints of the front of the trans to compare them yet, so I figured I would ask those that have been working on this far longer than I have.

Ryan
 

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Okay, another question.

Is the front (shaft and mounting surface) of this 05-10 T5 the same as the early Fox body one? I found a retrofit tail shaft housing that works on the earlier T5 but moves the shifter forward like the S10 and has improved oiling and other features in the tail area, plus it keeps it a slip yoke instead of a flange which isn't a huge issue, just keeps the shaft a bit simpler and lighter.

I haven't found blue prints of the front of the trans to compare them yet, so I figured I would ask those that have been working on this far longer than I have.

Ryan
As far as I know there are two types of bell housing to transmission patterns. Ford and GM.
I have the files for both, as I'm the one that designed them.

I don't know what the Fox body had.

In a GT, the driveline ends up really short. A slip shaft will work much better.
 

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Discussion Starter · #33 · (Edited)
I don't know the answer just yet, but this might be of some help:

Mustang T-5 Transmission Swaps and Interchange

EDIT: Found some more info from one of my earlier posts:

05-10 Mustang T5 Input shaft is 7.625" long and 1" diameter. It's a 10-spline shaft. Pilot shaft tip is 15mm (.588 = same as Opel) diameter and 15/16" long. Next 2.5" are splined.

and this:

https://www.stangnet.com/mustang-forums/threads/swapping-input-shafts-on-t5.891786/

Scroll down that page and you'll find a chart that should give you the info you need.

Short answer seems to be that both the length and diameter of the later T5 input shaft are different from the pre-2005 versions.
 

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Okay, another question.

Is the front (shaft and mounting surface) of this 05-10 T5 the same as the early Fox body one? I found a retrofit tail shaft housing that works on the earlier T5 but moves the shifter forward like the S10 and has improved oiling and other features in the tail area, plus it keeps it a slip yoke instead of a flange which isn't a huge issue, just keeps the shaft a bit simpler and lighter.

I haven't found blue prints of the front of the trans to compare them yet, so I figured I would ask those that have been working on this far longer than I have.

Ryan
As far as I know there are two types of bell housing to transmission patterns. Ford and GM.
I have the files for both, as I'm the one that designed them.

I don't know what the Fox body had.

In a GT, the driveline ends up really short. A slip shaft will work much better.
What I have found is that it looks like the main bodies for the Fords are the same, the later input is different but they are interchangeable and I have found a source for an after market S10 style front shifter tail housing to fit on the earlier Mustang T5. I am finishing up my 8 3/4 housing with 3 link suspension and will be getting rid of the torque tube any way so my drive shaft will be full length.

If I can get my hands on an adapter plate for the Ford T5 (or it’s cnc file) then I can piece a trans together with a drop in shifter setup needing no modification and the rear slip yoke keeping my shafr lighter overall.

Should work well under the mutt.
 

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I don't know the answer just yet, but this might be of some help:

Mustang T-5 Transmission Swaps and Interchange

EDIT: Found some more info from one of my earlier posts:

05-10 Mustang T5 Input shaft is 7.625" long and 1" diameter. It's a 10-spline shaft. Pilot shaft tip is 15mm (.588 = same as Opel) diameter and 15/16" long. Next 2.5" are splined.

and this:

https://www.stangnet.com/mustang-forums/threads/swapping-input-shafts-on-t5.891786/

Scroll down that page and you'll find a chart that should give you the info you need.

Short answer seems to be that both the length and diameter of the later T5 input shaft are different from the pre-2005 versions.
Great info, I found a bunch similar last night when I was up late because I couldn’t stop thinking about this.

One note I did find was that the input shafts are interchangeable so in theory the later one can swsp into a 90-93 body and then the aftermarke front shifter housing can replace the stock rear/mid shifted tail housing.

This will work out well in my case since I can use a longer tail, and slip yoke anyway with my torque tube going away.

I really appreciate this thread you started, I had been wondering about a T5 or other domestic transmission option for awhile.

Just need the plate or drawing for it now.
 

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Great info, I found a bunch similar last night when I was up late because I couldn’t stop thinking about this.

One note I did find was that the input shafts are interchangeable so in theory the later one can swsp into a 90-93 body and then the aftermarke front shifter housing can replace the stock rear/mid shifted tail housing.

This will work out well in my case since I can use a longer tail, and slip yoke anyway with my torque tube going away.

I really appreciate this thread you started, I had been wondering about a T5 or other domestic transmission option for awhile.

Just need the plate or drawing for it now.
You know the GM T5 works also, right?

Either way, we can work out something to get you an adapter.
 

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You know the GM T5 works also, right?

Either way, we can work out something to get you an adapter.
Yup, sure do.. but have better access to Ford ones.

I confirmed with my machinist that he can make one from either the drawing you have for the Ford T5, or from measuring the gear box and bell housing. I think I read where the thickness of the plate was 1 1/8".

If I can get the drawing for the adapter that would make it easier on this end and I wouldn't have to pay for shipping on the piece.
 

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Discussion Starter · #38 ·
Yes, 1-1/8" plate thickness if the input shaft is 7.625" long.
 

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Discussion Starter · #39 · (Edited)
Just a little update to this install.

I was never quite happy wth noise-vibration-harshness (NVH) levels since the T5 swap and decided to tackle that. The custom 2" exhaust I'd had installed prior to the swap was certainly noisier than the stock exhaust, but I also felt like there was some mechanical vibration somewhere, though I couldn't see anywhere where the exhaust was hitting the body. It turns out that a single bolt head on my cobbled-up transmission mount was resting against the bottom of the transmission just enough to create some mechanical vibration. The small block Chevy transmission mount I was using was also very hard rubber compared to the stock Opel mount.

The other day I happened on a forum post somewhere on the Internet that said that the T5 was installed in 1985-86 Chevettes, and since the Chevette is based on Opel underpinnings that gave me the idea to check out that particular T5 transmission mount.

It's Anchor #2391, and it was only $3.99 at AutoZone. At A.Z. they sell it under their Duralast brand with the same part #.

https://www.autozone.com/drivetrain/transmission-mount/duralast-transmission-mount-2391/555037_3854_6064

I had to drill a 2.5" hole in my crossmember for it to work, but it's lots more compliant than the Chevy mount and the engine vibrations felt through the floor pan are much improved. It attaches to the T5 with a single bolt, though I did have to ream out the center hole of the mount slightly for my Mustang T5 to mate up.

I do wonder if a Chevette transmission crossmember might be a good candidate to use for this swap. I do see them fairly cheap on E-Bay, but since my existing crossmember (from a Mitsubishi as I recall) is working for me I'm not inclined to investigate it further.

I wish the O/D 5th gear were not quite so tall (.72 ratio as I recall). It makes keeping up with traffic on the interstate a breeze, but would be more useful overall if it were a little shorter. Of course, 4th gear is the same 1:1 as the stock GT, so if I drop it down a gear I'm no worse than I ever was.

After more than a year of living with it I can say I'm not really a fan of the notchy T5 shifter compared to the original Opel 4-speed or the Getrag 5-speed. It works fine... just a personal preference. That's really my only complaint about the T5 swap.
 

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Glad to see that you found and fixed the gremlin.... I'm still a ways away from doing my conversion ...I'll have to reread the whole thing and try to make all the fixes so that I don't end up doing it over.
PS: Cam, I'll be getting to AZ in a week.
 
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