transmission clunking/chuncking

[brad1964]

My 1999 F150 XLT 4X4, auto trans, has a clunking/chunking noise when it down shifts or up shifts in low gears. It is most noticable accelerating after turning. I have had it in three times, they tell me it is normal. However, I noticed an excessive amount of end play in the drive shaft. Primarily as it comes out of the transfer case. I can see a witness line where the boot of the transfer case shaft has moved and left grease approximately 15mm mark (1/2 inch) on the shaft. Should this output shaft have that much free play? What is the spec for end play on the shaft? What could be causing this? Is it possible that a shaft thrust bearing has worked loose? I have driven a newer f150, with same engine/trans set up and have not noticed this clunk sound. Can anyone let me know if this is a serious problem? How do I fix it?

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[Joseangel2001]

I can't answer your question...I have the same problem. I have an 2001 F150 SuperCrew 4x4 Lariat, automatic transmission, got it in November and immediately noticed a clunking sound usually when it downshifts. I've got 10,000 miles on it. It doesn't do it everytime..its hard to predict. I'm due to go into the dealer soon but I want to load up first and see if its a known problem so I don't get BS'd. Any info would be appreciated. Thanks.

[2000F150FL]

I have also noticed an occasional clunk on the down shift of my 2000 (2x4) 4.6 Lariat auto trans. I have about 15,000 miles on it.

[Joseangel2001]

Folks, a lot of you seem to know about transmissions...who out there can help explain why new 4x4 trucks would have clunking transmissions...it cannot possibly be designed that way? What is recommended to fix it, and are there any serious consequences if it continues...anybody know?

[kkirt1]

I too have the clunking tranny! Someone said in the Crew forum that a Ford Engineer had contacted them about resolving this issue.

I had mine in the shop for several things they fixed. This one they said they forgot to check and to bring it back. That was right after they said it sounded like normal driveline play. Well I say BS.

I have also read about Ford replacing trannys, differentials and driveshafts with no luck. Has anyone gotten this fixed?

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Supercrew 4x4 Lariat
Solid Black , 5.4 Triton, 3.55 Limited Slip, 6750# GVWR Package, Skid Plates, Moon Roof, Sliding Rear Window, Trailer Tow - Class III, Cargo Cage, Grey Leather Captains Chairs, 6-Disc CD Changer

Mods:
305/70/16 Goodyear ATS
American Racing Atlas 16x8
Chrome Westin Steps
Flowmaster, Delta Flow 50 SI/DO
Cranked Torsion Bars 1"
Mobil 1 @ 1,000 miles
Concept II Deflecta Shield

Planned:
Toneau Cover
Expedition Console Mod. (Been there, done that - didn't like it so I sent it back! Be careful with L&W, they send out junk!)
kkirt1@hotmail.com

Another great Ford truck site -www.fseries.com

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[Joseangel2001]

kkirt1, where is the Crew Forum? By the way, my SuperCrew Lariat is black too, has all the options you listed. I think they are twins. I just ordered some Pinnacle Souveragn wax and am trying to get the bug **** off of it before I wax it. I'm thinking of buying some Python wheels, chrome. I can't believe Ford sells new trucks with clunking trannys.