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Yes, the TH400 intermediate clutches were waved. There are two output shafts (2WD) from GM for the 4L60E. The most common one has on the back of the output shaft a 6 line ID. The other one started about 2005-2006 that has a 3 line ID on the back of the output shaft. To make the 6 line ID hold up to more torque and horsepower. Have the shaft Cryogenically treated. The 3 line ID shaft is made of different material, is much stronger, and does not require this shaft to be Cryogenically treated. Use it as is. I have never had a problem with breakage on either one of these shafts. TransGo wants you to add the restrictors to the reverse input piston. Bad idea. Every transmission that I have seen come in as cores or rebuilds, that had the restrictors installed in the piston. Will have the steels having many Leopard spots all over them, and the clutches being somewhat burned. I do not use or put these restrictors in my rebuild kits. When you go looking for a 3 line ID output shaft. Do not tell them about what is discussed here. Once the parts seller is aware of the shaft being a better component. Will raise the price on them. I find them at around $35.00 to $50.00. In my opinion, they hold up just as well if not better than the overpriced Sonnax output shaft. As for the input shaft. I have never had a input shaft failure. However, GM made a better one starting around 2005 - 2006. First thing you will notice is the color of the input shaft is different than the earlier ones, more greenish grey in color. Second is the casting area between the machined areas has a wide dip near the middle of the casting area that is not machined. This shaft came both ways (with and without the reluctor teeth), and both will use the later stator support that uses the input shaft speed sensor. How common these shafts are. I do not know. The only Heavy Duty 4WD output shaft GM made, were the ones in the Syclone Typhoon 700R4 transmission. These are somewhat rare.
The customer opted for the Sonnax Output shaft & the Sonnax reaction shaft. I am using the OE hardened input shaft and the 4L79 drum. The one I got is the later more marbled one. FWIW, I have found that OE hardened shaft in 2003 & up 4L65E's. It became more normalized in 2005. Prior to 2003 all the HD input shafts I have seen had the wide band & were still darker in color or black. I'll post some pictures as soon as I can get back to my shop, right now I am a weekend warrior.
According to GM's 4L70E new product announcement the "input turbine shaft" is shared between 4L65E & 4L70E Item #9. In fact the 2 units shared every component listed with the exception of the reaction internal gear & the output shaft (one identification band).
Someone will whine about it but I make a billet spring retainer for the 4L60E reverse input and use HD springs for our new 4L60E Billet transbrake VB.
We also drill a bleed in the drum and plug the bleeds in the piston.
Other mods to the drum as well but they are more for the apply and release not centrifugal issues.
The funny thing about these forums is that knowledgeable builders are what attracts people to them. I don't know why any builder would pay to be here giving away advice, but the whiney MFers are the ones who I will never sell to.
My knees hurt to bad to go to the shop tonight and get the pictures of the input shaft & 4L79 drum. The Sonnax output shaft & reaction shaft showed up today. They look real nice, I thought I would post some pictures.
05-14-2024, 10:52 PM
