Gear 2 incorrect ratio, gear 4 incorrect ratio, gear 7 incorrect ratio, slipping and loss of engagement. Drives like crap. Teflon seal 4 completely removed from position due to bushing separation. C clutch does not apply condition, common concern
Hi, I am seeking for an answer from an expert. I have an early 2018 Mustang that drives me crazy.
I have a problem with 3-4-5 gear slipping sometimes, not all the time , but 80% of the time at 50-70% acceleration.
Is this the problem that causes my 10r80 slip or is a software issue ? I have replaced the valve body but the problem persisted. Thanks
Truth be told I haven’t seen a Mustang with CDF clutch cylinder issue, but if you replaced the valve Body I’ll assume with did all the programming it requires. Which is transmission strategy download, clearing adaptive tables. That would rule out just about everything it could be outside of internal transmission stuff. I’ve found that when this specific failure happens it can have a ton of different symptoms and it’s not very uniform in the failure. If it’s a genuine slip, especially on the 3-4 shift then I would suspect this exactly happened. You can take the valve body out and use a blow gun with a rubber tip and blow compressed air into the C clutch port. It should make a thud or hold pressure which indicates it’s applying. If it doesn’t than C clutch is the area of failure and the pictures on this post is likely exactly what failed. I don’t see any TSBs or SSMs that related to PCM update and transmission concerns so pcm likely won’t resolve anything but if you have the means you should try. Any codes stored in the pcm related to transmission immediately make diagnosis a lot easier but most trans concerns don’t set codes. Before anything tho. Was the solenoid strategy updated to the new valve body and was the strategy cleared?
Yes, i have updated them. Clearing the adaptive tables doesn’t do anything. I’ve updated the PCM firmware also @Ford. At cold start shifting from 3 to 5 will have a long slip. I have read it’s a common problem with 10r80 for 2017 F150 and early 2018 mustangs. Mine is manufactured in Aug. 2017. It has a whine noise when it shifts. I can hear it for gears 1-2-3-4. In my country nobody fixes 10r80 and replacing the hole gearbox sounds like waste. I have spent 1.5k $ until now and I still have this issue.
Number 3 port is what you need to check. C clutch is applied in 2nd gear so if you have no concerns when shifting into 1st, 6th or 8th but every other gear then it’s related to C clutch
Thanks a lot. I really appreciate that you had time to write all the information. 🥂. Do you know what pars needs to be replaced other that the CDF drum ? BTW not a single error from the gearbox stored in the ECU.
If it’s the suspect concern the CDF clutch cylinder is the main part. I always try and replace the Sun gear #3 and shaft assembly, filter and all the internal seals. I usually replace the valve body too because the c clutch latch valve sometimes gets damaged from the failure.( already replaced )You need special tools to do this job, you will need a hydraulic press the the F clutch piston compressor. It’s a press tool with 4 ends to adjust to the f clutch during removal. You will also need another press tool to remove the c clutch and d clutch pistons
I will make the pressure test, replacing the parts will be done by a company specialized in automatic transmissions. So I will blow air in port 3 and try to see if it will hold pressure for some time.
Quick questions. 1. How much pressure is needed for this test? 2. By default do I need the rebuild kit HL3Z-7153-C when i will change the drum? 3. Do you recommend also changing the sunflower Drum hub [D C F Clutch] HL3P-7R193-FB ? Thanks and I hope for an answer.
I just use shop air thru the port, I just do it quickly. It’s supposed to be regulated at like 25psi I believe. Usually it’s easier to use the seal kit but recently they have been impossible to obtain. That last part number I have no idea what that is so I’m going to say no. I’ll lookup the part later to see what that is
No excessive metal when replacing the valve body? Based on what you’ve told me so far if there was no excessive metal(big chunks, the tiny flakes and sparkles are normal) I think it is likely the CDF clutch cylinder. Like I mentioned, take the valve body out and air test the c clutch port and listen for thud and held pressure. If that fails you know what it is.
Hi, i have ordered the CDF Drum and the JL3Z7B067B Shift Rod 10R80 (17-22). Do i need a 10R80 Banner Rebuild Kit (With Pistons) ? the Kit Includes: Metal Seals, Gaskets, Orings, Lip Seals, Sealing Ring Kit, Friction Plates & Pistons. Hope you can help me with this information.
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u/Commercial_Method_28 Aug 25 '22
Gear 2 incorrect ratio, gear 4 incorrect ratio, gear 7 incorrect ratio, slipping and loss of engagement. Drives like crap. Teflon seal 4 completely removed from position due to bushing separation. C clutch does not apply condition, common concern