Transmission swap?

[Captain Steve]

What do you guys think about a transmission swap to a 5R55 5 speed Trans? It's the transmission that's in the new '05 Mustangs. I'm curious to see what opinions are.


Is that totally out of the question. If possible, what are the challenges? What do you think it would cost?



My thoughts are that I'm pretty happy with the way my car cruises on the highway with the 3.55 gears. But I'd love to have more grunt down low.

I've also wondered if it was possible to change the gear ratios in the transission the way you can in the rear end. A steeper 1st and 2nd might do the trick too.


Thoughts?

[Johng]

http://www.bigfastcar.com/default.asp

this is a successful company in the Washington DC area that converts the Impala SS to a 6 speed!

[snowbird]

What do you guys think about a transmission swap to a 5R55 5 speed Trans? It's the transmission that's in the new '05 Mustangs. I'm curious to see what opinions are.


Is that totally out of the question. If possible, what are the challenges? What do you think it would cost?



My thoughts are that I'm pretty happy with the way my car cruises on the highway with the 3.55 gears. But I'd love to have more grunt down low.

I've also wondered if it was possible to change the gear ratios in the transission the way you can in the rear end. A steeper 1st and 2nd might do the trick too.


Thoughts?PHP in Michigan did it for a one time effort with the stalker (Cobra crate engine and 6 speed manual trans (whole Cobra 2003 swap)).

I think the 5 or the 6 speed would be interesting to fit on our engine (the parts are available for mustangs) and it should be possible with a custom fit transmission crossmember, driving shaft and clutch pedal. I'm not shure about our cast crank VS the steel 8 bolt unit of the manual mustang's thought (Be it Mach1 or GT or Cobra) Also, another issue would be the electronics since the automatic trans is having a few wires wandering here and there for the various sensors. Swaping a manual might get the computer pissed off a bit. Yep, i think the crank and the computer are the 2 main issues. Some more knowlegeable than me on this board could clears those things thought.

The benefits would be a lot of fun and sportiness, and, some gains in the HP and TQ since the slush box is costing about 15-25 hp-tq loss over a manual.

[DTR04]

The 5R55 is a 5 speed automatic.

[MENINBLK]

The benefits would be a lot of fun and sportiness, and, some gains in the HP and TQ since the slush box is costing about 15-25 hp-tq loss over a manual.

It is a 15 - 25 PERCENT loss, not 15-25 HP-TQ loss.

[sfsv]

:) Folks the 5R55 trans is a 5 speed auto with a nice low 3.21 first gear ratio the 4R70w has a 2.84 first gear ratio. To the uniformed the Lincoln Aviator has the MM engine with the 5R55 trans. If anyone gets the chance drive this combination. You will find that under full throttle the engine does not fall below 3800 rpm's staying within the engine's power band. This trans does not that the beefiness as does the 4R70W. When you put the two trans side by side to compare them you will see the difference. Not to downplay the 5R55 transmission, I believe it would be a nice enhancement to a MM with the right tune and torque converter. Why torque converter? The early (2000 Lincoln LS) 5R55 torque converters had plastic vanes inside and I do remember the Ford engineers telling us not to brake torque these vehicles take it could cause serious damage to the torque converter and transmission. I honestly don't know what is inside of the latest 5R55 transmission torque converters or transmissions. As Lido will tell you that the 4R70W trans is virtually bullet proof when you install a Baunman shift kit and keep the transmission fluid within operationg spec's. By a matter of fact, I would love to see this combination inside a MM. It would make one sweet package.

[IMAX]

I have been thinking about the same thing. Whether a 5spd auto or a 6spd manual swap would be worth it. Also, couldn't you just beef up the 5R55 transmission? I'm interested in seeing what the rest of the responses will be.

[Captain Steve]

:) Folks the 5R55 trans is a 5 speed auto with a nice low 3.21 first gear ratio the 4R70w has a 2.84 first gear ratio. To the uniformed the Lincoln Aviator has the MM engine with the 5R55 trans. If anyone gets the chance drive this combination. You will find that under full throttle the engine does not fall below 3800 rpm's staying within the engine's power band. This trans does not that the beefiness as does the 4R70W. When you put the two trans side by side to compare them you will see the difference. Not to downplay the 5R55 transmission, I believe it would be a nice enhancement to a MM with the right tune and torque converter. Why torque converter? The early (2000 Lincoln LS) 5R55 torque converters had plastic vanes inside and I remember the Ford engineers telling us not to brake torque these vehicles it could cause serious damage to the torque converter and transmission. I honestly don't know what is inside of the latest 5R55 transmission torque converters or transmissions. As Lido will tell you that the 4R70W trans is virtually bullet proof when you install a Baunman shift kit and keep the transmission fluid within operationg spec's. By a matter of fact, I would love to see this combination inside a MM. It would make one sweet package.
Great info!

Going by this info, the 5R55 transmission with our stock rearend would give you an 11.39:1 ratio overall. The stock 4R70W transmission's 1st gear yeilds a slightly better 11.64:1 with 4.10:1 rear end gears.

So it would be nearly the same as having 4.10's.. but with an unchanged O/D.

[sfsv]

The advantage of the 5R55 trans is that the gear ratios are closer together, allowing less of a rpm drop when the trans upshifts, keeping the engine more in its powerband. Also with the low first gear it's like having the acceleration of a 4.10 gear with the fuel economy and top speed of a 3.55 gear. It's like having your cake and eating it to.

[Captain Steve]

Now for the real questions: would it just bolt right on? How tough would it be to convince our computers to work with it? Would a new drive shaft be needed? Would it be able to withstand the monster beating we'd put on it? :burnout:

[Captain Steve]

bump.

I would love to hear from DR or Lidio.

[IMAX]

bump.

I would love to hear from DR or Lidio.
Bump......

[MENINBLK]

Great info!

Going by this info, the 5R55 transmission with our stock rearend would give you an 11.39:1 ratio overall. The stock 4R70W transmission's 1st gear yeilds a slightly better 11.64:1 with 4.10:1 rear end gears.

So it would be nearly the same as having 4.10's.. but with an unchanged O/D.

Depending on when your Marauder was built, you may have the updated 4R75W transmission.

[juno]

Any new info on a 5r55 swap?

[Meteorite]

Bingo.

Those numbers (55 vs 70) relate to torque levels that the transmission can handle. So (according to Ford's nomenclature, which is approximate), a 4R75 will handle 36% more torque than a 5R55.



:) This trans does not that the beefiness as does the 4R70W.

[Zack]

A lot of times a trans that is advetised as a 5 speed is not what it seems.
The '5th' speed is sometimes used for decelleration only.
I am completely ignorant to the trans mentioned here, just adding some info.

[Mad4Macs]

Lidio wrote some interesting things about the new trannie, but they weren't things that would be cause to inspire confidence in its ability to handle more HP or torque.
I don't have a clue as to what "synchronous vs asynchronous" shifting meant, but the newer trans came off as sounding kinda weak.

[Meteorite]

What you say is true. The 5R55 is a legit 5-speed. However, it was developed from the 4R44E, and as such does not have a greatly increased "span" over the 4-speed, if I recall correctly.


A lot of times a trans that is advetised as a 5 speed is not what it seems.
The '5th' speed is sometimes used for decelleration only.
I am completely ignorant to the trans mentioned here, just adding some info.

[Meteorite]

The 2-3 shift in the 5R55 is not only synchronous (i.e., no one-way element such as one-way-clutch or mechanical diode), but it is what we call a swap shift, which means essentially that 2 independent gearseats must each be shifted at roughly the same time. This is very hard to pull off, and the higher the torque level, the trickier the timing can be.


Lidio wrote some interesting things about the new trannie, but they weren't things that would be cause to inspire confidence in its ability to handle more HP or torque.
I don't have a clue as to what "synchronous vs asynchronous" shifting meant, but the newer trans came off as sounding kinda weak.

[JACook]

The 2-3 shift in the 5R55 is not only synchronous (i.e., no one-way element such as one-way-clutch or mechanical diode), but it is what we call a swap shift, which means essentially that 2 independent gearseats must each be shifted at roughly the same time.
Synchronous shift, by definition, is having two or more mutually exclusive elements that must coordinate their
respective apply and release actions to perform a shift. And you're right, it's a difficult thing to orchestrate, especially
as loads increase. Back when I built the AOD/4R70W hybrid that's in my '93 LX, it took a bit of fiddling to eliminate an
annoying bit of tie-up during light-throttle 3-4 upshifts, without introducing flare when kicking back down. (BTW, the
AOD/4R70W/4R75W is only asynchronous between 1-2 and 2-3. The 3-4 shift is synchronous.)

Besides the synchronous shifting, the 5R55S is a descendant of the A4LD, which was in turn descended from the
C3. The C3 was first used in 4-cyl Pintos, IIRC. It's not a bad design, just not very beefy, being somewhat less
robust than a C4. Now, C4s could be built to handle quite a bit of power, so given modern materials and fluids,
maybe the 5R55S will end up being a good box. Or maybe it'll end up being like the AXOD and it's descendants
the AX4S and AX4N. (Anyone who ever owned a Windstar will understand...)

[larryo340]

A lot of times a trans that is advetised as a 5 speed is not what it seems.
The '5th' speed is sometimes used for decelleration only.
I am completely ignorant to the trans mentioned here, just adding some info.
I think that the 5R55 skips a gear on light accel, and on hard accel it hits all gears keeping the RPM up. No big RPM drops on shifts. At least that's what I remember when I had one in a '98 Explorer I had awhile back.

The 5R55's 5th gear is an actual overdrive:

Transmission Control Switch (TCS)
The transmission control switch (TCS) is a momentary contact switch that allows the driver to cancel operation of fifth (D) gear.
The TCS is located on the end of the selector lever.
When the driver initially presses the TCS a signal is sent to the powertrain control module (PCM).
The PCM uses the shift solenoids to disengage/disable fifth gear operation and activate the coast clutch.
At the same time, the PCM illuminates the transmission control indicator lamp (TCIL) to notify the driver that 5th gear is canceled.
When the TCS is pressed again, fifth (D) gear operation is enabled, the coast clutch is released and the TCIL is turned off.
Whenever the ignition is cycled (vehicle shut off, then started again), the TCS is turned off and fifth gear will be enabled, even if the TCS had been on when the ignition was shut off.

Here are the factory specs for stall speed on a '03 Explorer 5R55

Stall Speed Chart Engine RPM
4.0L 2,384-2,781
4.6L 2,598-3,025

[red]

You should do a six speed manual swap. I found one for sale here (http://www.mercurymarauder.net/forums/showthread.php?t=48520)! ;)

[FordNut]

Old thread alert!!

[red]

Old thread alert!!
d'oh! :o I was just, er, replying to the new post! ;)

[larryo340]

Old thread alert!!

http://images.art.com/images/-/Homer-Simpson--C10053426.jpeg


Oops, posted in wrong thread :o

[justbob]

But needed to be looked into again for any more input.

[Got Diesel?]

Sooo has this been done yet....

I thought I was being an innovator and found this thread

So has anyone swapped a 5r55 yet? It really sounds like a good deal if you go the Aviator route.

[justbob]

I think i'll tackle this option this summer.

[Got Diesel?]

If you do, keep us up to date on the progress.

[justbob]

Will do. I have already started gathering stuff.

[jfclancy]

Six speed S/C Marauder