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4R70E Overdrive....it's not the normal problems.
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crimsonride
New User
Oct 4, 2019, 3:42 PM
Post #1 of 4
(1976 views)
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4R70E Overdrive....it's not the normal problems.
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Hey guys,
So I'm helping a friend repair a no overdrive issue on his 2006 F150 4x4, 5.4L Triton. I believe this is a 4R70E. Anyway, he has no fourth gear, it just acts as if it goes in to neutral at about 35 mph or so.
The normal issues would be the overdrive servo cir-clip breaking, or the overdrive servo inner C-clip breaking and getting stuck in the valve assembly. ...Or possibly the overdrive servo not seated on the band properly. .....but I haven't found any of these issues when I pulled the servo assembly. I did find the separator plate has some hairline cracks so we replaced that with new gaskets after cleaning the servo assembly thoroghly. We also replaced the overdrive servo and clip just to be safe.
Anyway..... The problem still persists and I'm wondering if any of you more knowledgeable guys may know where else to look to solve this problem. It's starting to look like it's time to pull the trans out.
Any help is appreciated!
-Chris
(This post was edited by crimsonride on Oct 4, 2019, 3:44 PM)
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gsferraro
Veteran
Oct 4, 2019, 6:12 PM
Post #2 of 4
(1961 views)
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Re: 4R70E Overdrive....it's not the normal problems.
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Hello,
When you take the servo out, the band falls out of place, are you sure you caught the band putting the servo back in? If the clip did not break and the O/D servo reg valve is not stuck, change the piston itself, also make sure the bore is not worn out. Gary
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crimsonride
New User
Oct 5, 2019, 12:09 AM
Post #3 of 4
(1948 views)
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Re: 4R70E Overdrive....it's not the normal problems.
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Thanks Gary. We did replace the piston just to be safe but the old piston didn't show any signs of damage or wear. I did make sure the band was back in place and held before we installed the new piston.
Also, it isn't like fourth gear is slipping. It has nothing at all as soon as it shifts in to fourth....just spins like being in neutral so I don't think it would be the band being wore out.
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gsferraro
Veteran
Oct 5, 2019, 7:31 AM
Post #4 of 4
(1940 views)
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Re: 4R70E Overdrive....it's not the normal problems.
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Hello,
OK, still wouldn't rule out the band, I've seen them worn where I had no 4th(just did one a few weeks ago)
At this point the trans may have to come out to inspect the band. I have also seen a time where the direct drum was able to hold pressure in 3rd but not 4th. Gary
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