6T40 Rebuild 

Glad to help, thanks for watching.

Glad to hear it, thanks for watching.

Thanks. I was not saying that it is a problem. If it is the sprag noise, that is the noise they make. Also if it is the sprag, it will only do it in one direction. When it freewheels it clicks, the other direction it locks. The 3-5-R Cushion plate is also bad about breaking. It's a possibility that could be your noise. It does a tremendous amount of damage when it does.

Thanks for watching!

Glad it helped. Thanks for watching.

Hey mate, I’m wondering if I can pick your brain for a moment. I’m not a transmission worker at all and I’m a bit lost here. The reason I pulled my transmission out was I lost all forward gears, I still had reverse but no forward motion. I googled the issue and I watched some RU-vid videos and the suggestion was that it possibly was the valves(solenoids )in the transmission. I pulled those out first and tested them with ohms and power operation and everything seem to check out fine, but not under pressure.When I did drain the oil it was very black smelly and some little pieces of possible fibre. So straightaway I guessed the clutches were no good.. So I rebuilt it and a few of the clutches were no good. I stripped everything down and re-built it and drained the torque converter and flushed as much as the rubbish out as I could. Then reassembled. When I put the transmission back in the car it still won’t go forward. It has excellent reverse and it wants to go forward, when it is cold it will push itself very gently. needless to say I’m rather stressed as I need to get this thing going. My question is do you know what it possibly could be? Should I change the valve solenoids in the transmission, the seven pieces or do you think it might be something else. I replaced everything but I did not replace the Pistons. I replace the seals O-rings and everything else though.All the steels were in vg condition and nothing was broken or damaged. Any advice would be greatly appreciated.😕

You have a couple of options here. First thing to do is pull the valve body off and air check the drums. If they air check good you probably have a bad techm. The part that contains the computer and solenoids. It will need to be programmed after installation. To air check the drums. The 2 rubber tubes that were installed under the valve body in the case. Top one is Low/Reverse, bottom is the 1-2-3-4. The 1-2-3-4 is probably where your problem is as you still have reverse. They are bad about blowing out. As you are looking into the case, far right. There are passages that look like they lead outside. Top one is 4-5-6, next down is 2-6 and the next is 3-5-R. If any check bad and the unit needs to come back out I suggest you replace all the pistons. Also did you replace the 3-5-R cushion plate? If not and it needs to come out replace it also.

@@CurmudgeonTransmission thank you so much for this. I will let you know how it goes!! Thanks again.

Thanks for that, I did just pull the sump cover back off. The two channels that go behind the plate in the middle of that with the rubber tubes,they both check okay and are operating normally. I put air into the side passages as you suggested the top one doesn’t do anything just blows out elsewhere the second one operates normally and I can hear a Clutch or a piston engaging. The other two underneath that don’t do anything. When you say replace the Pistons. Do you mean the seals that go on the bottom mount where those air channels go to,inside the drum? Because I did replace them when I pulled the transmission down. Obviously they’re not seated right or not engaging properly though. Do you reckon they could be my issue or still need to replace the techm? I did forget to mention that when I lost all forward gears in the leading up to that i.e. the 45 minutes or so before they failed it would not go above fourth gear. So I could only use 1234 and the transmission would not engage five or six. Thanks Brother..

Thanks. What exactly do you mean by swelled up? You got a picture or a video you can post on your page?

@@CurmudgeonTransmission basically the rear sun shell seems to have stretched out. The 3-5 clutch splines are loose inside the shell and the clutches on the outside of the shell are stuck.

@@CurmudgeonTransmission I just posted a video of the Sun Shell. And thank you for taking it to reply to me. I really appreciate it.

Glad it helped

Thanks

Thanks.

Thanks!

I would before it gets too bad. These can go from not much damage to catastrophic in a very short time. I'm glad you have had good success with yours. I have the same year and it has been nothing but trouble. One of the worst cars I have ever owned. As soon as I can I will be getting rid of it.

⁠​⁠@@CurmudgeonTransmissionyou know that’s what I heard that these cars have been nothing but issues. So far the car hasn’t given me any real major issues besides the transmission shifting poorly. Other then that it’s been honestly more reliable then I would’ve ever thought. A few small annoying issues I see with the car throughout my years of having it , the valve cover gasket keeps leaking so I bought a new valve cover. Maybe the old one was warped. Also the car always seems to be needed it’s overflow tank to be topped off with coolant every few months. I never see puddles on the ground or smell like coolant is being burned. That’s pretty much it. I did replace the usual components that cause coolant leaks and such but have no clue where the coolant is going. That’s why I’m considering rebuilding the transmission because other then that , the car has been fairly good to me. What’s the average mileage you’ve seen with these 6T40’s lasting out of curiosity ? I been changing the fluid every 30k miles since I’ve owned the car.

@@MachineGunner29 Somewhere around the 100k mark.

Thanks for watching.

Thanks

Thanks

I get that alot. No I don't, Every builder I know does not do it either. Not near as critical as everyone likes to make it. I will do it on a racing transmission and it is a carry out but other than that no.

Thanks

I am not sure. Always safe to follow recommendations. Having said that we are using a full synthetic and they have been working fine.

Gold is transgel, green is Dr. Tranny. Thanks for watching.

Transtec, and I believe this one had Exedy Clutches. I prefer Raybestos or Borg Warner clutches but that is what I got.

I have not had a 6T50 in the shop yet, and only a handful of the 6T40's. Which is weird because we get a ton of the 6F35's.The internals will be set up the same. The difference is going to be in hard parts. The planets I would think would be heavier duty. Different sprocket tooth counts which would probably make for a different chain. Differential, sun gear and ring gear probably. The rest I would think would be the same. So pay close attention if replacing any of those parts.

Thank you for the information and quick reply!!! @@CurmudgeonTransmission

I found it.. the dowels get stuck.. but thank you!

89 in. lbs + 50 degrees. It has a molded gasket for the case, so if you don't replace it, put a thin bead of silicone on each side of it. Don't leave it off or your end clearance will be off.

Thank You.

Bushing driver. www.toolsource.com/bushing-tools-c-1321_119_581/bushing-driver-set-solid-steel-19pc-p-92045.html?tsqtid=63701

WIT or Transtar. Links are in the description.

We get our parts from WIT or Transtar.

Google translate has not made it very clear what you are asking but I think you are asking about putting fluid on the pump gears. You can if you want to, not a bad idea.

It is recommended.

Most states you have 30 days to take it back. Try to make them pay for it or get out of the deal if you can. I have a Cruz which has the same transmission. Worst car I have ever owned, worse than the Hyundai Elantra I had. Will be going bye-bye as soon as I can make it happen. The 3-5-R cushion plate always breaks and causes a ton of damage. Even though it is basically the same as the 6F35 that Ford uses,they always seem to be in worse shape as far as damage goes. Every one I have had come in has been so damaged that it was cheaper to get one from Chevy. Mine included. Mine went out about a year ago. They will give you a 3 year 100,000 mile warranty. Was right around 5K for parts and labor.

None that I am aware of.

If it has never been rebuilt it is time before a lot of damage occurs. If it is after a rebuild I would be looking at the valve body or Techm.

@@CurmudgeonTransmission thank you. Could the 1-2-3-4 piston be cracked?

Techm selonaid valve team new.

Never seen one crack but it may have been damaged when installing it.

Probably high 3's to mid 4,000. Depending on the damage.

​@@CurmudgeonTransmission если перевсти в рубли... То я не плохо съэкономлю 🤣🤣🤣

106 in. lbs.

@@CurmudgeonTransmission Thanks 👍

One more question, on the video 20:10 there when you grease with brush around the edge where piston sits , on my 6t30 that edge is bit shaved on the top due to wave plate destruction under input drum , Do you believe that I have to replace whole rear case or it can be used again? I’ve ordered input drum pack and master rebuild kit. Basically input drum is damaged and that case edge on the bottom is slightly shaved on the top, all other parts survived.

That is going to be a judgement call. When that plate breaks it does tend to ruin the case. If you think it may be bad it probably is. It may work for a short time, but now is the time if you have doubts. Awful lot of work to go back when you are right there.

@@CurmudgeonTransmission 👍

Thanks

Thanks

When it first cracks, maybe not. After a piece breaks off, yes.

Jan Palmer 2 hours ago I drove for 200 miles, since I heard the oily clicking sound, clicking sound when rolling forward just 12 inches, engine off, but the 2010 chevy drove good, no shudder, no eratic shifting, no slipping, no limp mode, or check engine light, should be alright, thanks for the advice.

Two things come to mind. The first is the diode sprag. It will make a clicking sound like that. The other is the park pawl, however it should be heard all the time, and probably would have park problems also. Are there any other problems with the vehicle? If you want to make a video of the noise and send me a request on my Instagram I will take a listen.

drives good no problems at all.

I will let you know, what the problem is, in a couple hours.

If it is driving good it may just be normal noise the sprag makes. I would just need to be able to hear it.

Thanks for watching!

​@@CurmudgeonTransmission скажи пожалуйста если будут вопросы могу ли к тебе отбратиться за советом?

Yes. No problem. Thats what I'm here for.

@@CurmudgeonTransmission 👍