2001 Expedition Faulty Diode? or Simple Fix? HELP..PLEASE - Diesel Forum

rtd2 · 10-23-2006, 12:18 AM

Hello and thanks for reading
have a 2001 expy EB Build date 2/2001 with a 5.4L I LOVE.. Great Maint records and ALL Synthetic fluid! It has the 4r100 tranny (code "e" on pillar) 76,800 MILES. (tanny has Yellow marking on it and G1 code on a white sticker) a year ago I started getting a Shudder(like rumble strips) in OD so I did a Pan off Fluid/filter change (including torque convert) and refilled with 16qts of Royal purple ATF. and it shiofted GREAT...NOW last week (1 year and 16,000 miles later) I have a Delayed 1-2 shift with a chatter sound on acceleration. Bad enough I either have to let off to force the shift or it will run up to 2800-3200 rpm's before shifting with a slight jerk/squeal. all the other shifts including O/D are fine. I just did ANOTHER fluid change 2 days ago but this time I had it power flushed at local shop and added 16qts of valvoline MAX life fluid (Meets Mercon specs as I need shop didnt have anything better). THIS DIDNT HELP as the chatter and delayed shift is still there.(chatter is like spinning a spoked bicycle tire and placing a playing card in it) Also Noticed if I punch it into Passing gear the RPMS race up and tranny doesnt catch till RPMs get back around 4000RPM. If Placed into 2nd with shift selector ..it is VERY weak!OD light has NEVER blinked and Button works (turns OD on/OFF) seems ford has a TSB#01135 that covers the Delayed shift symptom. AM I on the right track with 1-2 shift Accumulator broken spring DIY fix OR could it be BE THE dreaded mecahnical diode? NON-DIY fix...I thought IF the Mechanical Diode FAILED it was low mileage fast if at all?(as Indicated BELOW in another forum...) Is it woth the trouble to pull the pan and check the 1-2 accumalator spring to rule it in or out or take it in? I know if its the Mechanical diode (ONE WAY CLUTCH) I'm facing a TOTAL rebuild! local TRUSTED shop quoted a Mechanical Diode-one way clutch total rebuild around 1300.00 and if its just the accumalator spring 250.00...Any ideas? THANKS!!! [img]/ubbthreads/images/graemlins/shrug.gif[/img]
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http://www.f150online.com/forums/sho...one-way+clutch

Casey_1 · 10-23-2006, 08:12 AM

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could it be BE THE dreaded mecahnical diode?

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It's very doubtful that it could be the mechanical diode, since those were only in 4R100s behind the 7.3L. No Expedition with a 5.4L got the mechanical diode.

rtd2 · 10-23-2006, 07:13 PM

[ QUOTE ]
[ QUOTE ]
could it be BE THE dreaded mecahnical diode?

[/ QUOTE ]
It's very doubtful that it could be the mechanical diode , since those were only in 4R100s behind the 7.3L. No Expedition with a 5.4L got the mechanical diode.

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Man I wish that were the case...Thanks for the reply and Info. ITS TOAST NOW! I just dropped it off at local tranny shop. HAD to LIMP there , Chatter noise got Worse and was present even in Neutral. I Lost drive, 2 and 1 had to Shut off the truck and restart several times to get it to catch a gear by the time i made it! 12 miles took me 35min!....Owner is a friend of the family and assured me its the Mecahnical Diode -sprag. He said he's done no less than 10 of these. ( including his sisters 01 Exp 5.4 )that early died last year with 52,000 on the clock! Still dissapointed but he said no more than 1300.00 to rebuild and thats with a 24/24 warranty. Truck looks and drives new Everything is fine just got back from vacation with it and now this. Its paid for so its worth fixin. Thanks again Hope to have it back by thursday

Casey_1 · 10-23-2006, 10:11 PM

It's the intermediate one way clutch. This trans didn't get the mechanical diode. Only the diesel trans had that problem. If the intermediate one way fails, it's the same as the mechanical diode failing. The fix on the diesels is to replace the mechanical diode with the one way sprag clutch design that your trans has. It isn't failure proof, either, but it is a lot better than the diode type clutch.

I'm sure it isn't any consolation that it's a sprag type clutch that failed, not a mechanical diode, but that's what happened.

rtd2 · 10-23-2006, 10:19 PM

[ QUOTE ]
It's the intermediate one way clutch. This trans didn't get the mechanical diode. Only the diesel trans had that problem. If the intermediate one way fails, it's the same as the mechanical diode failing. The fix on the diesels is to replace the mechanical diode with the one way sprag clutch design that your trans has. It isn't failure proof, either, but it is a lot better than the diode type clutch.

I'm sure it isn't any consolation that it's a sprag type clutch that failed, not a mechanical diode, but that's what happened.

[/ QUOTE ]

Casey,
I stand corrected. thanks for explaining. Now that I've had time to think about what the tranny guy said he seemed to hint of what you said (About Diesels and Gassers Diode/sprag)but what was key was he said the fix is to go BACK in time and retofit the trannys to 2000 models.Hopefully I can get better results out of the rebuilt tranny! Thanks again for your info. and time!