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Need help finding transmission transplant expert 2

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CustomCadi

Automotive
Mar 31, 2004
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I have been searching the net for 4 days looking for information and have come up with nothing. I believe if anyone can help me, it is you guys here...

Here is the deal... I just bought an '02 Cadillac Escalade AWD 6.0L Vortec V8. I don't like the automatic transmission, and what I would really like to do, is transplant the "Sportronic" 5-speed automatic w/ clutchless manual shifting transmission from an '02 Mistubishi Montero Limited into the Escalade. My first question, is can this be done? I understand that there would have to be modifications to the Escalade, and most likely some parts would need to be fabricated. I haven't been able to find a diagram of the Montero tranny to see if its even remotely close to the design and size of the Escalade tranny. Is this something that can be done at a custom shop, or is this a project that most engineers would shy away from? Money is not an issue, and neither is time. I am hoping that this is something that is relatively able to be done, and that I can find a shop that can do the work. Any help or input would be GREATLY appreciated!

Thanks in advance!
-Brandon

 
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Not a good idea for several reasons. The input torque specs, trans mounts, shift linkage, output shafts, and the killer, ecm interface. Recommend you modify the existing trans, what's your beef with what's there? Bub
 
I agree that the ECM is probably a killer. There are similar situations where people want to switch over to a manual transmission. It is easier to transplant the engine and transmission complete from a manual donor vehicle than just swap trannys. Perhaps this would work for you - the 2004 4WD 2500 series truck can be equipped with the same engine you have and a 5 or 6 speed manual. Unfortuantely, you would need the whole drivetrain because your AWD system is incompatible.

An equally serious problem is torque capacity. The Mitsu uses a 223ft-lb V6 compared to the 380ft-lb V8 in your Caddy. This is a huge difference. Companies that reinforce transmissions (like Level 10) can work magic but this is asking an awful lot. BTW, that manual shifting stuff is no real trick - it's just giving you control of what gear the automatic is in.

Could I propose that you start small. Try a Transgo Kit or a higher stall torque converter. Your transmission is a modified version of the automatic in the Corvette so there should be plenty of options. Depending upon what it is that you don't like about the trans, maybe we can address the more specific problems.

Best 'o luck - Scott
 
Thank you both for your responses! I was actually concerned about the difference in HP between the Montero and my Escalade, because not only do I have the 6.0L, but I also added a Vortec supercharger in it. It currently has a top end HP of around 585 with a few other mods I did to it. The thought did cross my mind that the Mitsu tranny would get ripped up pretty fast.

Ok... so where do I go from here? The transplant idea is a no-go. Its not that I have a particular "beef" with the tranny that it comes with stock, but my fanatical love of the Sportronic transmission. I want the ability to have the car in auto when I want, and to be able to manually control the gear without a cluth or the "H" pattern shifter when I want. My previous car was an Alfa Romeo 166, and the best thing about that car, was its Sportronic transmission... I fell in love with it, and now I want that same drive control with my Escalade. I'm willing to pay/do what I have to to acomplish that. Here is a little description of my old Alfa Romeo tranny from ItalySpeed:

"First and foremost, the Alfa 166 automatic transmission offers 5 dual-purpose speeds. You can use the normal P, R, N and D positions when the lever is moved up in the gate. When in D position, however, all you have to do is move the lever to the left, into the areas marked 'plus' and 'minus' and the automatic device converts to a sequential manual gearbox with all the freedom that can offer, including the ability to set off in second or third
when the car is driven over slippery ground."

So is it possible to modify the existing Caddy transmission to do this? I would imagine it would have some sort of computer control? I really wish I could get my hands on some exploded view diagrams of one of these trannys... I can't find one piece of info on them anywhere!

Again, any and all help is GREATLY appreciated!

Thanks again!
-Brandon
 
The OEM trans repair book would be your best bet, hydraulic flow diagrams, ecm interface, and line pressures, but hard to find. Mitchell On-Demand trans repair has less info. I believe some Benz trans start off in second gear at light throttle. You might end up with a electrically controlled trans with no mechanical shifter at all. Bub
 
It seems clear to me that somebody can rig up a sport shift or possibly paddle shift; if you think a sport shift is cool you'll love a paddle shift. It's all a matter of tricking the electronically actuated hydraulic valvebody into thinking you've moved the shift lever. With enough money anything is possible. You're surely not the first person to want to do this - try a high end corvette shop for help.

However, you're not going to have as much fun as you did in the Alfa for the simple & lamentable fact that your transmission is a 4 speed. I have a 5spd tiptronic that really helps keep me in the fun zone on a turbo motor. A 4 speed would provide larger differences in the rpms between gears and give you one less choice; less choice = less fun. In a 4 speed you might as well be turning the OD button on and off.

I should mention that with a blower, you have given a death sentence to the transmission. That's not a bad thing really because every failure is a chance to upgrade. Just be prepared that the end will come. You can talk to the guys at "Level 10" about how to make it stronger.
 
Thank you both once again for your follow-ups!

I checked out Level 10's website, and I think they are a great place to start. I will definitely use them to "bullet proof" the tranny as they put it. I'm building this thing to be a real monster, and if I am going to go through the trouble of modifying the tranny, I want it to last, because I am definitely going to cane the nuts off of it.

Harris, I understand what you are saying about the 4-speed, but thats actually ok with me. I don't mind giving up a gear, I mainly want it so that I can drop down a gear when in 4th or 3rd and accelerate to get a torque burst forward. The difference in RPMs is what I'm looking for for that extra boost. It REALLY helps knowing that it is a modified corvette transmission, that knowledge will come in handy I'm sure. Whats a paddle shift? I don't believe I've ever seen or heard of one of those...

You both have really helped point me in the right direction, and when I started this project, I would have never thought to modify the existing tranny (didn't know it would be possible). If I could get someone to rig a sport shifter that would be ideal... if not, maybe I can canibalize a Gamecube controller and mount the buttons on the steering wheel somewhere... that would be pretty sweet.

Thanks again for all your help!
-Brandon [thumbsup]
 
Paddle-shift was originally intended to allow very fast gear changes under aggressive driving conditions. With your hands on the wheel you can use paddles to shift gears in similar fashion to how you use your turn signal. You find them in Ferraris, M3s, etc. BMW people are now retrofitting these modified steering wheels into 3/5/7 series.

In all honesty, for most people paddle shifters are a gimmick just like manual shifting automatic transmissions. Similarly, both features are harmless fun for the Nintendo generation.

Enjoy! Scott
 
I hope no one minds this being a tangential post, but CustomCadi, you mentioned you've got your Escalade up to 585hp or so. I have an '03 Escalade EXT with a vortec supercharger on it, accompanying new injectors, exhaust, etc. and have it to about 550-555hp. What other additions have you made in order to increase your power output? I'm looking around for the "next step" in getting mine over the 600 mark.

- Tony in MA
 
your transmission is a GM 4L60E and was never designed for the power you are trying to generate. It is basically the same unit used in a Vette. The real difference is the wieght difference that your Escalade has over the Vette. There are after market units that are better and will shift on demand, but still lack substance due to their inherent design. If you do get the transmission to respond as you want you will also have to address the transfer case and both front and rear differentials as they use the same common GM corporate units found in basic 4 wheel drive GM vehicles that use a fulltime system.
 
Mike, you're correct on each count of course.

If we try to design stuff that won't fail under the foot of a 95th percentile driver we'll mostly succeed. However, if somebody increases torque into the 4L60E by 25%, I would expect the transmission (bearing) life to decrease by about 1/2 - and this asumes that there are no critical overloads, no heat problems, no clutch pack problems, no drive shaft problems.

The question really comes up after the fact; after somebody has dropped $5-10k into a blower, etc. Then the question is how can we keep the car on the road. Coolers and shift kits help reduce clutch wear and temp issues but I don't know anybody in the aftermarket that will change the gear or bearing designs. There is no one I would trust to upgrade an OEM AWD viscous clutch. After all, a brand new drivetrain costs less than some spinner wheels and I've seen guys buy several sets a year.

Note to super charged caddies: do not do any heavy brake loading at a stop light - you'll walk home.

Have fun! - Scott

 
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