Turbo 400 Build

[hotrodpc]

For the purpose of knowing what a center support is supposed to look like, here is photo of one in its normal condition. You can tell the color of the parts, which part with the springs have been destoyed by comparing the pics. And the 1 above of the center support still in the case.

There some of the destroyed pieces, and you can see some of the case lugs. Amazingly, none were broke or damaged. Probably the case saver with the help of the center support not being able to move save it. If this were a Turbo 350, I feel certain the case would have been trash or had to use aftermarket case savers which I refuse to use.

This is how a center support is supposed to look. A bit differant from the above huh??? CARNAGE !!!

 

[hotrodpc]

Here are all the assemblies removed the from the transmission. Now we get to start taking assemblies apart and find out what really went wrong. Notice the band is no longer round. I did that trying the get the trans apart when it was stuck, so that carnage don't count. However, it needed replaced anyway because of heat in this transmission, even though there was plenty of meat on the band, it was very brillte and the fibers were flaking off, so no harm done.

 

[davbell22602]

Nice pictures. I guess that 3t40 will look something that when I tear it apart.

 

[hotrodpc]

Nice pictures. I guess that 3t40 will look something that when I tear it apart.

That all depends what came apart Dave. I have pulled non working transmission apart that looked gorgeous inside. Example being. You have a pump failure and the pump quits working, then nothing can compress or apply and nothing can burn up and the vehicle not able to move, no carnage is going to be found. Its rare to see them in this bad of shape. Especially a Turbo 400 in a stock vehicle. Now, this could happen in a high performance vehicle that does not have the proper updgrade, and it stems from hitting 2nd gear to hard or to much weight and hitting 2nd to heavy. That will NOT be happening to this transmission ever again. I'll explain when I get to the part. Remember above, I said I upgraded 1 little part for $25??? This will NOT happen again due to that part. This trans is ready to rock with whatever I want to pull, even a 14,000lb back hoe on a 2500lb trailer. This trans will handle it, even with 3.21 wussy wagon gears and a good trans cooler.

 

[hotrodpc]

Now with the trans case gutted, its ready to go to the local trans shop and put in the washer to be cleaned. I will be getting my money's worth out of this one. It pays at times to help people out. I did a process service for this guy who was a friend of a friend and was divorcing his wife for emptying out their bank account and he did not have $50 to serve her yet. She was trying to leave state with his kids and time was of the essence to get her served. So I served her for him and said we'd work out the payment details later, just take care of your kids. So that was done. He happened to have been a manager at a trans shop a mile away and I remembered that. Guess how much it cost to get cleaned??? You guessed it !! $0.

Below is the center support without the parts that were destroyed. Notice after all this damage, and 173,000 miles the center bushing is like new. Somewhat common in a 400. The center support keeps everything inline and gives no room for flex to either one side or the other, no matter how much torque is applied.

 

[hotrodpc]

Here is more carnage, why the trans would not come apart as it should have, and the actual failure that caused the domino affect for other damaged parts.

Intermediate clutches, steels and pressure plate where welded together caused by the below failure.

Here is the major initial problem. BROKEN SPAG !!! This gets beat on going from 1st to 2nd gear. This is why it needs to be upgraded for street/strip applications. Most hotrods, hit 2nd gear pretty hard with alot of torque, higher rpm, and alot of force especially if I built the trans, and especially with a full manual valve body. This was no hotrod truck though. Just a stock 454 carrying a good load and 173,000 miles of wear.

You can see the sprag gear is wedged and cocked on the drum, which turned the steels and clutches sidways and started the overheating and burning from this point right here due to broken sprag. If it was not for being a tight fit, this gear would have came off, but it couldn't. I never did get the gear off. I trashed the whole drum. It was toast.

 

[hotrodpc]

OK, the case is now as clean as its gonna get. This thing ran 4 time thru the washer, still looked like hell, so I had to buy some commerical dereaser that eats skin to get it this clean. I had to call it good enough and live with it as is. Now that you seen all the fun stuff, and all the carnage. Its time for the boring stuff. The rebuild. Stay Tuned !!!

 

[dirtyoldman]

Love the write-up so far Now you get to put it all back together

 

[hotrodpc]

Love the write-up so far Now you get to put it all back together

Thanks Gramps. This is like one of those TV Cooking shows. Where they mix all the ingredients, throw it in the oven for 5 seconds and pull it out completed cooked dish. This trans build already has close to 5000 miles on it already. But for purpose of the thread, nope its not done yet. Damn, now that the cat is out of the bag, no need to watch the finale huh???

 

[hotrodpc]

Being that transmisison was going to need several hard parts replaced, I figured it would be best to find a donor trans for the hard parts. I got on CL and hit up all the Turbo 400 sellers that were $100-$150 and asked them for the code on the side of the trans. One Guy came back with a CE 69. That told me the trans was out of a 69 Chevelle Big Block SS Car. I was wanting a 69 or older transmission because 69 and older have the smooth race direct drum for use of the much stonger dogbone wedge element sprag instead of the weaker roller style. The guy was wanting $150 for it, but when I asked for the code, he emailed me back with the code and said he needs it out of his way, he'd take $100. Guess he didn't know yet, I was buying it. So I got out there to look at it, knowing its a passenger car trans. I looked at the output shaft for threads, wo me saying a word, he says, I know, thats why I am selling it, it was for my rockcrawler build but it doesn't have a threaded shaft for the yoke, thats why I am selling it and everyone needs threaded shaft for trucks, so if you can use it, I'll throw in the Torque Converter too and take $50 to get it out my way. I never asked the guy to go down on the price, he was just desperate to get rid of it. He told me it worked fine, that it came from a buddy of his old car that was converted to a 700r4. It had been rebuilt before, I was just hoping it had the good sprag in it still. But for the price, I was buying it for sure and did.