I have two II's, one is a 1978 and the other is a 1976. The 78 is in decent working order where as the 76 needs work and i've hit a snag in my build. I've read that the stock 4 speed the "RAD4" as it's called is not the most noted transmission for holding up to a warmed over 302. I need to know what I can possibly swap in without much trouble or how I could make the RAD stronger. I don't want to use a T5 seeing as it would just blow up behind my engine anyway. I've read about the RUG Swap on the II organization but I wanted to see my options. Also, i'm not made of money. I belong to AFM is anyone recognizes me.
I am in need of 4 speed transmisson information.
- Thread starter MustangIIJunkie
- Start date
-
Sponsors (?)
Steel Steeds
New Member
Why do you say the T5 would blow up? That is by far the most common swap into a II. I've got one behind my built 351W, and there is a wealth of information on how to do it. The only other manual transmission I've seen put into a II is a toploader, but I don't have any info on how easy/difficult it was.
I'm not aware of any way to make the RAD-4 stronger.
I'm not aware of any way to make the RAD-4 stronger.
I've put a wide ratio RUG in a II, with a little grinding on the doughnut rar the stock manifolds work.
The oversize bell may require spacing the radius arm bracket cross member back a little (in one car it didn't , in the other car it did).
RUG shifter needs spaced back 1 1/2 inches more or less. I've done that 2 ways using an old Hurst.
What else ...
Hydraulic clutch is the easiest way to get the old bell fork moving.
Bright spot of the RUG is the trans cross member comes close to lining up, bitch is I don't know what motor mount bolts up (I forget which one I used).
...
Oh yeah, 1-2 shift rod comes real close to the body pan splice in the tunnel. May/ May not need massaging.
I needed a longer drive shaft.
I ditched the RAD before the T-5 made its' appearance so this is all IIRC.
The oversize bell may require spacing the radius arm bracket cross member back a little (in one car it didn't , in the other car it did).
RUG shifter needs spaced back 1 1/2 inches more or less. I've done that 2 ways using an old Hurst.
What else ...
Hydraulic clutch is the easiest way to get the old bell fork moving.
Bright spot of the RUG is the trans cross member comes close to lining up, bitch is I don't know what motor mount bolts up (I forget which one I used).
...
Oh yeah, 1-2 shift rod comes real close to the body pan splice in the tunnel. May/ May not need massaging.
I needed a longer drive shaft.
I ditched the RAD before the T-5 made its' appearance so this is all IIRC.
How built are you talking because all my Fox friends tell me a T5 won't take hard driving with an over 300 Ft pound engine without getting the crap kicked out of it. Not to mention install can be a pain. Why didn't Ford just use a proven Manual instead of a wussy one. I think i'm just going to stick with the RAD and see if it breaks if it does. I'll access the damage and if it's something simple like an input shaft I'll have one made out of something stronger.
My problem with the RAD wasn't the gearing or strength of the transmission.
The transmissions didn't stay in reverse very well, and the single rod shifter setup ... it didn't work very well for some of us.
And what your buddies are telling you about the T-5, the first T-5s were weak but they were made progressively stronger.
I guess their still pretty wimpy compared to a RUG. But then most car transmissions are.
The transmissions didn't stay in reverse very well, and the single rod shifter setup ... it didn't work very well for some of us.
And what your buddies are telling you about the T-5, the first T-5s were weak but they were made progressively stronger.
I guess their still pretty wimpy compared to a RUG. But then most car transmissions are.
Steel Steeds
New Member
Wart's right, the T5 improved every year. The one I put in is an NOS '93 Cobra unit, the best of the factory T5s. You can have one built that will hold up to just about anything other than blatant abuse. Anything will break if you beat on it hard enough. My 351W is running 10.5:1 compression, Comp Cams .555"/.576" lift cam, AFR 185 heads with 2.02"/1.60" valves, Holley 770 Street Avenger. Should be good for close to 400hp and at least that much torque. I've only got 400 miles on the setup, so I haven't pushed it at all yet. Next summer I will get it dyno'd and take it to the track a time or two to see what it will really do. But, I'm not going to beat on it, so I'm confident the tranny will be just fine.
78CobraII
Moderator
I'm guessing that that last bit was irony...
The T-5 install into a MII does have its challenges, but probably less than the RUG Top loader.
In the case of the T-5 swap, you can at least stay keep your RAD bell housing and flywheel (if you choose to go in that direction). The RUG requires a top-loader style bellhousing.
Another possibility is the 3+OD trans used in the early Fox Mustangs. Its nearly as strong as a RUG, because its basically a toploader changed over to a single rail shifter. Hopefully its shifter works better than the one in the RAD...
In fact I've broken a RAD behind a 2.3L, but likely it was due to poor shifting on my part. Some of it was likely due to wear in the shifting mechanism though.
A T-5 can be built plenty stout, in fact, several companies specialize in it. For example: G-Force Transmissions and Long Shifters
D&D Performance will sell you either a rebuilt hardened T-5 or a new from Tremec "World Class" tranny. Its capable of handling over 300 ft lbs.
Welcome to D&D Performance - The 5 & 6 Speed Experts!
Of course if you are doing either all-out road racing or repeated full throttle drag racing launchs, you should consider another transmission. A built toploader for road racing, or a built C4 for drag racing.
Make sure you carry a gun to a gun fight!
I plan on taking this car to the strip 2 or 3 times a year. What exactly broke in the transmission? Does the power just strip the gears or what? What is this other 3+OD transmission you are speaking of? I don't understand what you mean by irony though. Another problem I have is that money is short. I'm already halfway into my build budget when I learn the tranny ain't so hot to trot with power.
78CobraII
Moderator
The irony is that many other MII owners are trying to get OD so they can get better gas mileage on the highway. With a drag race friendly 3.55 or lower rear gear, you can expect 4000 rpm at 70 mph.
My problem was probably due to shifter fork wear. Eventually it can get so bad that you get the gears jammed. Also it can get such that it won't hold in reverse. Poor downshifting was my cause...i.e. downshifting at too high of a speed, and getting the shifter in the wrong place. If you are upshifting in standard fashion, it will hold for a while. If you are dropping the clutch, granny shifting, or hurrying your shifts in any way, you can expect failure.
If you really want a reliable drag trans that makes repeatable shift times, grab a functional C4, add a shift kit, new seals, and new clutches. Probably less than $500 for the whole thing. Almost any C4 will do (small and medium Fords '68-'79), but you will need the MII bellhousing, flexplate, and TC to bolt it up without mods. Keep it in mind that the bellhousing, block plate, flexplate, starter, and torque converter all have to come as a package. If you end up with an earlier C4, bellhousing, flexplate, and TC, the mods are actually no biggie, just remember to get the set. A functional C4 can likely be had for $100. With a little work you can find one that someone has already modified that will last you a season.
The 3+OD was a transmission based on the RUG (Toploader) that used an internal shift rail instead of the earlier external shifter rods. And its a 3 speed plus 1 OD gear instead of a 4 speed. Its pretty much as tough as a RUG. It does require the standard RUG bell housing though.
Lots of MII/302 owners are looking for good 4-speed parts, so you are likely to be able to sell it all. You may even find someone with a C4 setup that will swap even with you.
My problem was probably due to shifter fork wear. Eventually it can get so bad that you get the gears jammed. Also it can get such that it won't hold in reverse. Poor downshifting was my cause...i.e. downshifting at too high of a speed, and getting the shifter in the wrong place. If you are upshifting in standard fashion, it will hold for a while. If you are dropping the clutch, granny shifting, or hurrying your shifts in any way, you can expect failure.
If you really want a reliable drag trans that makes repeatable shift times, grab a functional C4, add a shift kit, new seals, and new clutches. Probably less than $500 for the whole thing. Almost any C4 will do (small and medium Fords '68-'79), but you will need the MII bellhousing, flexplate, and TC to bolt it up without mods. Keep it in mind that the bellhousing, block plate, flexplate, starter, and torque converter all have to come as a package. If you end up with an earlier C4, bellhousing, flexplate, and TC, the mods are actually no biggie, just remember to get the set. A functional C4 can likely be had for $100. With a little work you can find one that someone has already modified that will last you a season.
The 3+OD was a transmission based on the RUG (Toploader) that used an internal shift rail instead of the earlier external shifter rods. And its a 3 speed plus 1 OD gear instead of a 4 speed. Its pretty much as tough as a RUG. It does require the standard RUG bell housing though.
Lots of MII/302 owners are looking for good 4-speed parts, so you are likely to be able to sell it all. You may even find someone with a C4 setup that will swap even with you.
A regular C4 bell works with stock manifolds with above mentioned removal of metal from the dough nut ear on the right manifold.
I hear aftermarket headers can be made to clear.
About money, both the old top loaders and new T-5 are expensive. I honestly don't know which would cost more when it's all said and done.
C4 or AOD would be the least expensive.
I hear aftermarket headers can be made to clear.
About money, both the old top loaders and new T-5 are expensive. I honestly don't know which would cost more when it's all said and done.
C4 or AOD would be the least expensive.
As a P.S.
When doing major component replacements such as transmissions and axles I've found it best to replace as a unit.
For a trans it would be from engine plate (and pilot bearing) to output yoke.
That way you know you have a component made of components that are known to work together.
An additional benefit is when ordering parts you know what to order parts for, keeps the parts jockey from getting too confused (I've actually started by telling them I was ordering parts for three different vehicles. The stories .... )
I myself, if doing the T-5 swap, would just use the Jox bell, that would make a solid bolt up to the engine and eliminate the pilot bearing issue. Now it WILL place the shifter another ... 1/2 inch? .... forward but isn't it already ~ 1 1/2 inches forward? Shifter should be relocated anyhow, relocate it further.
And IIRC there is a supplier of relocation kits for single rod shifters so there you go.
When doing major component replacements such as transmissions and axles I've found it best to replace as a unit.
For a trans it would be from engine plate (and pilot bearing) to output yoke.
That way you know you have a component made of components that are known to work together.
An additional benefit is when ordering parts you know what to order parts for, keeps the parts jockey from getting too confused (I've actually started by telling them I was ordering parts for three different vehicles. The stories .... )
I myself, if doing the T-5 swap, would just use the Jox bell, that would make a solid bolt up to the engine and eliminate the pilot bearing issue. Now it WILL place the shifter another ... 1/2 inch? .... forward but isn't it already ~ 1 1/2 inches forward? Shifter should be relocated anyhow, relocate it further.
And IIRC there is a supplier of relocation kits for single rod shifters so there you go.
84 5.0
the 1984 5.0 was one of the fastest 5.0's every built from the factory and if im remembering correctly they pushing close to 325 at the rear wheels if not more while run the t-5 trans.and all you would have to do is is pick a bell housing should bolt right up with out a probems as well as the through out.how many different bolt patterns werer accculy put on 302 thrugh the years? the problem is the tunnel clearance isn't big enough .so you would have to some handy dandy hammmer fabercation to get to fit better or its a real pain in gut the trany to force it in and putting the bolts in at the same time.if your worned about not having enough balls behind your motor them try to find yourself a t-6 from a mid 90's cobra and build it . they do make bell housing that adapt to the correct trans to motor .
the 1984 5.0 was one of the fastest 5.0's every built from the factory and if im remembering correctly they pushing close to 325 at the rear wheels if not more while run the t-5 trans.and all you would have to do is is pick a bell housing should bolt right up with out a probems as well as the through out.how many different bolt patterns werer accculy put on 302 thrugh the years? the problem is the tunnel clearance isn't big enough .so you would have to some handy dandy hammmer fabercation to get to fit better or its a real pain in gut the trany to force it in and putting the bolts in at the same time.if your worned about not having enough balls behind your motor them try to find yourself a t-6 from a mid 90's cobra and build it . they do make bell housing that adapt to the correct trans to motor .
Steel Steeds
New Member
Ah, come on man. Do a little research. The '84 5.0 was rated at 175hp AT THE CRANK. That's roughly 149 at the wheels.
There's no such thing as a T-6. The T-56 didn't show up until 2003.
I could go on, but I think you see what I'm saying.
There's no such thing as a T-6. The T-56 didn't show up until 2003.
I could go on, but I think you see what I'm saying.
king combo
Founding Member
I just had my rad 4 rebuilt at One of the best tranny shops in the city. I just wanted one final run of the 4 speed before I go for the t-5. But a poor prior rebuild, and a few boo boos on my own part let to it's demise, but it was behind the 351 for a good 6 years. Even bigger bonus, the rebuild only cost me $250 cash! I'll keep u posted if I blow it up once I get her back into the car. FYI-V-6 casing with V-8 internals. Ya a real gem of a combo lol
It was the input shaft bearing that seemed to die first for the RAD4's I went through. I was killing mine with abuse, powershifting and what not with a 9:0 compression, 4bbl, stock headed 302. The first two RAD4's died in one year of daily driving. The T-5 has survived swapping to an '88 5.0L with plenty more power, 2 more years of daily driving, a few drag races with 10" slicks, and 8 years of occasional driving. I even munched an 8" pinion bearing (which munched the gears) with abuse delivered through the T-5.
The big word in the way I drove it is: "Abused". I'm pretty sure the RAD4's would've been fine without the powershifting and hard launches.
A Tremec 3550 is also an option and pretty much the same as installing a T-5. That's how I fixed my abusive driving issues for my 351W.
The big word in the way I drove it is: "Abused". I'm pretty sure the RAD4's would've been fine without the powershifting and hard launches.
A Tremec 3550 is also an option and pretty much the same as installing a T-5. That's how I fixed my abusive driving issues for my 351W.
Steel Steeds
New Member
Similar threads
