Best High-po Tranny?

I shift my tko600 over 6000rpms, never had an issue. Know plenty of others that do it too.

There is alot of rumors about it shifting poorly above that rpm, but few people that actually use a 600 that complain of it.

Now i don't know my real shift points and i drive more by feel and sound than by visually looking, mainly because if i'm at 6000rpm i'm probably on the car pretty hard and don't want to land up in the bushes.
Also i use a tach adapter to run the stock tach, it's accurate at low rpms, but who knows up top. But i do know my power holds past 6000rpm so...

Taken from Tremec literature:

Do not attempt to shift the transmission when the engine is revving over 6,500 RPM’s.

I didn't even add the underline. The TKO was never meant to be a high RPM transmission, at least in stock form.
 
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Taken from Tremec literature:



I didn't even add the underline. The TKO was never meant to be a high RPM transmission, at least in stock form.

6000 and 6500 rpm are kinda far apart for the average user. Engines with minor mods can exceed 6000rpm, takes a built engine to exceed 6500.

I by no means am saying it's good for 7000rpm, because i truly don't know, but you guys were saying 6000rpm is the max and i'm not sure that's an accurate depiction. 6500, well i guess that could be though.

Mine is a good 6-8 years old now, and i've never had a shifting issue of any kind.
 
I shift my 3550 at about 7000, definitely needs a firm slam of the shifter though. Mine has never shifted into fifth to easy at high speed, I'm not sure what RPM I usually go into 5th at, but its probably well under 7000.
 
You can also buy a TKO tail housing, but it cost about $550. It's much more efficient to bore the old one. That is to convert your old 3550 to the old TKO specs. the new TKO600 also has a one piece countershaft. On the 3550 and old TKO, the countershaft consists of a shaft with individual gears pressed on with key ways. I don't know if it makes a huge difference in strength, because it's usually the teeth that break. I have broken both. I have snapped teeth off of the 3rd gear set, and I had the key way shear on the drive gear on the counter shaft. You can find a used one piece countershaft on ebay for decent prices. Be careful to watch for different gear ratios. Different versions of the transmission have different gear ratios. Obviously a one piece countershaft with the wrong gear ratios will not work. I don't think swapping to a one piece countershaft is worth it. Surprisingly, just about the only piece I have not broken in my 3550 is the original 28 spline output shaft.

Kurt
 
As for the high rpms shifting, it is a common problem. The 3550 is not really a drag racing transmission. I never had much problem getting it to shift, but I never go over 6500 rpms. I just did the carbon fiber lined blocker ring upgrade on 2nd, 3rd, and 4th. The blocker rings were $60/each. It definitely shifts faster. I couldn't tell you how high in the rpms it will shift well at though. Bob Hanlon would be able to give you a better idea. I have heard that anything over 7000rpms, and you pretty much have to get the engagment mechanisms faceplated.

Kurt
 
Probably not, but anytime you can put more information into each post, it saves time in the future. Someone may end up with a high rpm solid roller engine, and want to get more information on the transmission. Since this is a sticky post, they will likely come here first, and find the information they need.

Kurt
 
6000 and 6500 rpm are kinda far apart for the average user. Engines with minor mods can exceed 6000rpm, takes a built engine to exceed 6500.

I by no means am saying it's good for 7000rpm, because i truly don't know, but you guys were saying 6000rpm is the max and i'm not sure that's an accurate depiction. 6500, well i guess that could be though.

Mine is a good 6-8 years old now, and i've never had a shifting issue of any kind.

In fairness, it doesn't make much sense to drop coin on an aftermarket trans like the TKO and not put it behind a built engine.

You can also buy a TKO tail housing, but it cost about $550. It's much more efficient to bore the old one. That is to convert your old 3550 to the old TKO specs. the new TKO600 also has a one piece countershaft. On the 3550 and old TKO, the countershaft consists of a shaft with individual gears pressed on with key ways. I don't know if it makes a huge difference in strength, because it's usually the teeth that break. I have broken both. I have snapped teeth off of the 3rd gear set, and I had the key way shear on the drive gear on the counter shaft. You can find a used one piece countershaft on ebay for decent prices. Be careful to watch for different gear ratios. Different versions of the transmission have different gear ratios. Obviously a one piece countershaft with the wrong gear ratios will not work. I don't think swapping to a one piece countershaft is worth it. Surprisingly, just about the only piece I have not broken in my 3550 is the original 28 spline output shaft.

Kurt


I have to imagine that the multi-piece cluster shaft allows for more flexing, which would lead to broken teeth. Surely the enginerds at Tremec had a reason to go to the solid cluster when they came up with the new generation of TKO 500/600.
 
I talked to a friend today who will sell me his whole project for $6000. Includes a new tko 600, clutch, and 363 Dart short block, which is all I really want, also comes with a used big Vortech blower, (not sure which model), "igloo" type intercooler, ported Trick flow heads, (again not sure which ones but I believe they're the original Trick Flows), B-451 cam, steel scattershield, and a 1994 Gt roller. Body is okay but nowhere near pristine, has some light rust on body seams underneath. Seems like to good a deal to pass up but I don't really have the money to spend!
 
I talked to a friend today who will sell me his whole project for $6000. Includes a new tko 600, clutch, and 363 Dart short block, which is all I really want, also comes with a used big Vortech blower, (not sure which model), "igloo" type intercooler, ported Trick flow heads, (again not sure which ones but I believe they're the original Trick Flows), B-451 cam, steel scattershield, and a 1994 Gt roller. Body is okay but nowhere near pristine, has some light rust on body seams underneath. Seems like to good a deal to pass up but I don't really have the money to spend!

That's great but does all of that really belong in this thread? You should post that in it's own thread in the General Talk section or maybe in an intro post in the Welcome Wagon.
 
I'm rolling over 7 with my 3550, actually 7500. It is a late 3550 as it has many of the features as the TKO. I have a chewed 3rd gear sycro from being to gentle. You really have to hate the trans to work at higher rpms.
Scott
 
Personally, I'd go with the TKO. I'm not sure how bad a C4 would be on the highway without overdrive.
I don't know about indestructable. I've destructed mine several times. I suggested the TKO for ease of installation since he had no preference. Also it has an overdrive.

Kurt
The TKO 500/600 is a great transmission and can be built to be damn near indestructible, but a word of warning- in stock form, the synchronizers are marginal and start to struggle with shifting above ~6K RPM. This is part of the reason why you hear so much griping about the TKO's shift quality. All of the big name transmission companies- Astro, D&D, Modern Driveline, etc. offer solutions to get them to shift like butter at 6500 and up, usually by installing carbon fiber lined syncros and modified shift selector fingers.

Sometime next month I am going to detail the rebuild of my TKO 500 with some "sure shift" goodies from Astro... Stay tuned.

sorry for the late reply guys, been pretty busy with school lately. That being said, i'm on a pretty strict budget. I've heard some good things about ford t56s, what do you guys think of a [re]built t56? or would it be in my best interest to save up and buy a TKO or AOD?
 
I've been through this several times with customers. Here's the deal with the T56....it's expensive. It really boils down to what you want to do with the car. Just about any way you slice it, it ends up costing around $4k to get a T5 or aod out of a Mustang, and then end up driving away with a T56. If you really want a 6 speed transmission, then the T56 is by far the best option. If you don't ever drag race the car on sticky tires, the T56 will work just fine. It you don't have a cam with really fat lobes, the T56 will give you better gas mileage, and less noise while cruising on the highway. That is where the fairy tale ends. It has an unrealistic reputation for strength. the T56 and the 3550 series are built to the exact same technical specs. That is to say, the gears are the same width and strength, and the bearings are the same diameter. In short, the 3550 series and the T56 are equal in their abilities. The reason the T56 gets such a good reputation is simple. It came stock in the Camaro, and for every 1 Camaro that is drag raced on sticky tires, there are 50 Mustangs doing the same with a T5. It's just a perception thing. The TKO600 will cost you at least $1000 less..eh, probably even a greater savings than that. For those of us who have quite a bit of torque, the price points are much better on the TKO stuff as well. Since most Camaro owners don't race their cars, they don't break as often. In this case, less demand means lower production volume, means much higher prices. The price points on T56 parts are approximately 3 times that of a 3550 series. For example, a 26 spline input shaft on 3550 is $68 on ebay right now. The same 26 spline input shaft on a T56 is $330. So every time you break your T56, you are going to end up spending 3 times as much as the guy who broke his TKO.

Kurt
 
The price of a T-56 swap is coming way down, you can do them for much cheaper than 4k if you buy the parts smart. Im also going to call BS on them not being any stronger than a TKO. How many guys have been in the 8's with any TKO? As far as i know, one, the x2c motorsports car. Everyone that tries usually breaks multiple transmissions shooting for the record, and these are light race cars with adjustable clutches that are going for it. Now the T-56's have multiple cars deep into the 8's and are still running strong, and as far as i can tell most of these cars are not as light as the cars that are breaking TKO's.
 
There have been lots of cars in the 8s with TKOs. I have had both transmissions apart on my bench side by side. They are virtually identical.

Kurt
 
There have been lots of cars in the 8s with TKOs. I have had both transmissions apart on my bench side by side. They are virtually identical.

Kurt

Who did it? Do you have any photo/video/timeslip evidence of the TKO's in the 8's. There is a whole 8 second TKO thread on corral and everyone is still chasing the x2c 8.99 second pass. Virtually identical or not, the real world has proved that the t-56 is a stronger transmission. The case is the weak link in all the TKO transmissions, it seems like once guys start going mid to low nines with em the cases crack quick.
 
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Believe what you want. If you have that much power it's a good idea to put a case girdle on the transmission. Cracking problem fixed. Call up TTC, and they will correct your misconception.

Kurt
 
I have a case girdle, people still crack them with girdles... i dont need to call TTC, im just going by what happens in the real world. Seen a few camaros, vette's, and one fox with a t-56 in the eights.

I am still waiting to see the answer to who the "lots of cars" in the 8's with a TKO are also......