[Lscman]

What parts are needed to convert the '79 2.3L turbo 2bbl carb cars to work with an '87 and up 4cyl normally-aspirated 2.3L T-5 gearbox? Did Ford screw with the flywheels with respect to tooth count or oz-in imbalance or bolt pattern or rear main seal design or input shaft pilot hole that could screw me? I'm a pessimist & knowing Ford, this may not be a plug and play swap.

I seem to recall these old turbo cars used an oddball aluminum BW 4spd instead of the cast iron case german WT 2.3L tranny. The RPM drop between 3rd and 4th is HUGE, unlike the german tranny that had nicely spaced gears. I'm thinking the stock 3.45 diff gear will be OK with the T-5 OD gearing. I seem to recall the turbo carb'd cars had a unique flywheel and clutch assy. The clutch always seemed to be stiffer than a normal n/a 2.3L.

Any advise about differences in starters, clutches or flywheels is appreciated. I am using a complete '88 Mustang 4 cyl T-5 car as a parts donor for my '79 Turbo car, so miscellaneous parts are a non-issue. If the '79 engine imbalance and crank bolt/pilot bearing pattern is IDENTICAL to later EFI cars, I can simply swap in the whole T-5 setup...flywheel & starter etc. Anyone confirm this?

I am clueless about the 2.3L...sorry for high post count on day 1 (lol). Well, at least I'm not bailing for the 5L world.

[Lscman]

I guess not much is known about the 2.3L cars. This is why folks choose the 5L route.

[T&C-stangs]

From what i understand all you need to bolt on a t-5 is the pilot bearing where the input shaft goes.

[Lscman]

Well.......

A unique pilot bearing is indeed needed to swap a 4 cyl tranny into a V8 car and vice versa. This is because the input shafts differ.

What I'm not sure of is the subtle variations between various 4 cylinder cars with respect to driveshaft, flywheel, starter, clutch, clutch fork, throwout bearing and other issues that could impact a 4 to 5 spdde 4 cyl tranny swap.

I thought maybe some 4 cyl fanatic here would know.

Thanks for replying though!

[mfpmax]

You'll need basically everything that it takes to convert an auto to a manual. I do believe the pedals are even different for the 79-81 cars, but not certain. The Bellhousing is different, the clutch cable is different, the driveshaft is different.

[Lscman]

I got some info on another forum...thought I'd share it here.

The all-aluminum RAD 4spd tranny used in 79 Turbo has the same bell pattern and input shaft design as the later T5. A 4 cyl T5 will slide right in and allow the old RAD bell, clutch, cabling and flywheel to be retained. How un-Ford is that?? In fact, it's almost unbelieveable. I guess the Mustang II and Fox 200 cu in I6 owners love that, since those cars came with RAD's too! As a bonus, a pilot bearing adapter is sold that allows a more common V8 T5 tranny to be utilized instead. This gives you flexibility to choose more ratios too.

A small number of 2.3L carb turbo cars were shipped with the pinto-ish German iron main case tranny and this easy retrofit plan does not apply....wrong input shaft, wrong bell etc.

Folks caution that the T5 is sightly longer than the RAD, so the driveshaft length is marginal. Some folks had luck reusing the Rad driveshaft and other's did not. One person noted that the slight difference between a 7.5 and 8.8 differential made enough difference to require the driveshaft swap. My guess is some owners may not realize the yoke is jambing the output shaft at full suspension jounce. You'd probably be safer to find a T5 4 cyl driveshaft for this swap or get yours shortened by the exact difference in tranny lengths. The yokes are the same diameter and spline. It would be interesting to see if they are the same length.

[5.0ForLife]

Is there such a thing as a T-5 for a 4 cyl? Or is it the same tranny as the 5.0's
use? If so, what year did the T-5 show up in the 4 cyl? I just can't see a 4 cyl
having the same T-5 as a 5.0. My present mustang has the 3.3L I6. So, your
saying I can bolt up a T-5 out of a 91' GT to my 3.3L with no problems? If so
this is good.

[stokstad]

I put a T5 in my 86 LX. I had the crappy 4 spd RAD trans in it. The T5 I got was out of a Tbird I believe. It didnt come with a bell housing so I had to get a 4Cyl T5 Bell and a new driveshaft out of a newer 5sp mustang. I believe the clutch will work but I got a new one for a T5 4 Cyl car. It all installed fine. Bolted right up. The rear crossmember was a little tight but it worked as well. The only thing I had to do was make a custom link for my clutch cable. The Rad trans just had a ball that slipped into the release fork. the T5 bell had like a bell crank deal on it. I just made an L braket and secured the original cable to the new Bell crank deal. Has been working great so far. I really love having a 5spd in there. Even though I have a gutless 2.3 N/A engine. Also its not recommended to put a 5.0 T5 with a 4cyl engine as the ratios are different and I think it makes them even more gutless.

Oh and one more thing I had to cut a bit of metal out where the shifter comes through the floor. About a 1/2"

Also the RAD driveshaft will not work with the T5 as the slines on the yolk are different.

[Lscman]

Originally Posted by 5.0ForLife

Is there such a thing as a T-5 for a 4 cyl? Or is it the same tranny as the 5.0's
use? If so, what year did the T-5 show up in the 4 cyl? I just can't see a 4 cyl
having the same T-5 as a 5.0. My present mustang has the 3.3L I6. So, your
saying I can bolt up a T-5 out of a 91' GT to my 3.3L with no problems? If so
this is good.

Here's some help:

1) Some 3.3L I6 came with RAD tranny ('79 to '81 or so). Other 3.3L I6 came with RUG tranny during the same timeframe. It seemed to me that Ford was putting the stronger RUG (SROD) into Fairmont cars, although I did see Mustangs of that era with the 6 cyl OD tranny. I know both trannys were used behind the 3.3L for a fact because I help my buddy pull his RAD and bell and switch to RUG with overdrive with bell. I sold him the 3.3L RUG/SROD with bell for $100. Boy, talk about highway gearing.
2) The 5.0L came with RAD tranny (Mustang II).
3) My '79 2.3L T came with RAD tranny ('79-'86).
4) All 5 speed 4 cyl Mustangs from '87-'93 are T5 and they are fairly plentiful.
5) Ratios in T5 vary all over the map. You can find this info on-line.

Fox cars (including 3.3L) with a RAD tranny are ALREADY equipped with the correct bell housing for a T5 swap. Folks who don't figure this out are swapping to newer clutch linkage and doing everything the hard way. The early RAD clutch cable system is the simplest and it's 100% compatible.

Now on the topic of T5....

All T5's are not created equal, but tons of 4 cyl 2.3L T5's were produced. The 4 cyl version is weaker and service parts for rebuild are harder to obtain. Most 4 cyl versions have wider gearing in 1 thru 4 positions to get the gutless car moving from a standstill & their OD gear % drop is generally not so steep (0.8x vs 0.68). Go to T5 sites for specific gearing by model/year/engine. For a torquey 3.3L with it's somewhat narrow powerband from 1200 RPM to 3500 RPM, you might be better off with closer V8 gear ratios (with the 3.35 first gear, instead of 4.xx).

Any '84-93 2.3L T5 (turbo or non-turbo version) from Mustang or TBird will pop into the RAD bellhousing with the right pilot bearing. T5's that specify thinner ATF fluid instead of GL5 80W-90 gear lube have "World Class" cage bearings under the gearsets for improved life and efficiency. This is customary since the middle 80's in manual tranny designs. Since the RAD tranny is marginally shorter, you may need to shorten your driveshaft to install T5. Simply measure precisely from the machined mounting face of the tranny (where it attaches to the bell) to the end of the output spline. The difference between the two trannys is the exact difference in driveshaft length needed. A driveshaft shop will do this for about $150.

If you prefer to use a more common & stronger 5.0L T5 in a 2.3 car, you simply need to use a special $10 pilot bearing aftermarket adapter for V8 T5 in 2.3 car. The 4 cyl and V8 T5 input shafts are the same length, but the pilot tip beyond the spline is a different diameter. Externally the V8 and 2.3 tranny is identical (aside from pilot bearing centering pin), including input and output splines.

I do not know the OD dimension of the 3.3L pilot bearings where it taps into the crankshaft. This is the only unknown you will need to deal with. A sleeve can likely be fabricated allowing either the 4 cyl or V8 tranny to be fitted. Use of a modern type needle cage bearing pilot bearing is not mandatory. Cars used bronze impregnated sleeve pilot bearings in this application through the 1970's (50+ years) and they work fine for 200K miles. You can get those type of bearings in any size and they can be machined to any ID/OD dimension using a common lathe.

[5.0ForLife]

Thanks a lot you guys. That's alot of good info. A couple more questions...
Is the RAD a 4 spd manual? Is the RUG a 4 spd manual? What is the 3 spd
auto in my '81 called? What would the 4 spd manual in my '86 2.3L have been called?

[Lscman]

Originally Posted by 5.0ForLife

Thanks a lot you guys. That's alot of good info. A couple more questions...
Is the RAD a 4 spd manual? Is the RUG a 4 spd manual? What is the 3 spd
auto in my '81 called? What would the 4 spd manual in my '86 2.3L have been called?

RAD is a light-medium duty all aluminum 4 spd with no overdrive that's found mostly in Mustang II and Mustang from somewhere around 1975 through 1986. In the Fox, it was never used with a V8. My memory is fading, but I think this was sourced from Borg Warner.

A tiny, unique German 4 spd tranny with no overdrive is also found in some Fox 4 cyl non-Turbo cars. It had a cast iron main case and aluminum tailhousing. It came from the Pinto. This tranny had a high spline count, instead of the normal 10 spline input shaft.

RUG/SROD is a medium-heavy duty 4spd with overdrive ratio in top gear. It's found in various Fox cars. It is a descendant of the overdrive transmission found in Granada & Monarch in the mid-70's and earlier, strong top loader Ford 4spd found in older higher powered Fords of the muscle era. For Granada, Ford redesigned the shift system to flop the order of 3rd and fourth gears. In the later overdrive configuration, the OD 4th gear is actually 3rd with a ratio under 1:1. Aftermarket tuners figured this out and did some interesting things with this tranny by blending old toploader parts and later aluminum single rail shift housing. This tranny was manufactured by TREMEC (Transmissions of Mexico). It's design was updated again in the late '90's to add-a-gear, giving us the notorious biggie TREMEC 5spd that sells in the aftermarket TKO etc, used in Cobra.

Three 3 spd auto trannys were used in Fox, referred to as C3, C4 and C5. I think the C5 is an update of one ofthe earlier designs with a locking torque converter added. You'd need to crawl underneath and identify what you have by looking at the pan shape etc.

Around 1985, Ford began using the AOD overdrive automatic tranny in Fox V6 and V8 cars. This is the same tranny found in all years of Mark VII.

Around 1987, Ford began using the light duty AXOD automatic overdrive tranny in 2.3L Fox.

[5.0ForLife]

Thanx again. So will a C3, C4, or C5 bolt up to a 5.0 with no problems?
If so will any or all of them hold up to the power of a stock 5.0? Is the
AOD the same for 6 cyl cars as the 8cyl? If so, it's awesome how
interchangeable all the parts for these cars are.

[Lscman]

Originally Posted by 5.0ForLife

Thanx again. So will a C3, C4, or C5 bolt up to a 5.0 with no problems?
If so will any or all of them hold up to the power of a stock 5.0? Is the
AOD the same for 6 cyl cars as the 8cyl? If so, it's awesome how
interchangeable all the parts for these cars are.

Different auto trannys are designed for different engines. Generally the V8 RWD cars built in the last 30 years got C4, FMX, AOD or AODE, depending upon vintage, motor and car model. The big C6 3spd was obolete by mid 70's as the AOD 4spd OD debuted. The C3 & AXOD are light duty tranny for low power...not V8. The later C5 was overshadowed by the AOD with it's extra gear. Not too many folks interested in 60's technology with no OD 4th ratio for street automatics these days.

Almost every 6 cyl has a unique integral bell housing....that goes for 2.8L, 3.3L & 3.8L. Forget interchanging.

Automatics are fairly off topic........

[5.0ForLife]

Thanks again. You've answered all my questions.