4r100 problems

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Jun 25, 2015 | 10:34 PM

BC.7.3L

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4r100 problems

Hi guys. Im a newb when it comes to this forum, deisil, and tranny. I bought a 2001 7.3L deisil F250 CC short box a year ago. It has an AFE cold air, a 4inch exhaust and... 😨 an Edge chip in it.😣 Now the tranny was rebuilt a year before I bought it, however I almost instantly noticed a shutter when starting from a stop. One shop said u joints. I replaced them and the carrier with no results. IMHO u joints was a bad diagnosis as it only happens off the line and not through at a certain rpm. When down shifting I find the truck almost goes into to neutral before engaging 2nd gear. I have a 6.0l tranny cooler and my temps get to 215 and above quite easily when towing... 3-6k-lbs. (I try to pull over before that) Also when towing up hills the tranny almost feels like there's a slight grinding. For the first little bit anyway. Any ideas or suggestions will be appreciated. Also cam anybody suggest a good tranny shop near Vancouver Canada? Sorry for the massive post.
Thanks
Nick

Jun 26, 2015 | 05:26 AM

Mark Kovalsky

Frmr Ford Trans Engr

Joined: Aug 1999

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From: SE Florida

Shudder from a stop is caused by driveshaft misalignment or bad u-joints. I don't know how a transmission would cause that.

When you say it almost goes to neutral downshifting, what do you mean? If it almost goes to neutral, do you mean it doesn't go to neutral and downshifts normally? That can't be it, because why would complain about that? So does the engine RPM go too high at the start of the downshift, then go lower as the shift completes?

There is no reason to cool the trans at 215. That's warm, but well within normal temperatures. Where is your temperature sensor located?

Jun 26, 2015 | 06:16 AM

BC.7.3L

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I've replaced my u joints and the problem remains. It's my understanding that u joints or drive shafts problems will occur at a certain rpm in any gear that you are in.

While down shifting the truck will coast, drop rpm, and then engage into the lower gear. Engine drag disappears for a second before it goes into gear.

Also I've been told by several people not to let your tranny get up to 215 otherwise you'll cook it.

Jun 26, 2015 | 09:50 AM

Mark Kovalsky

Frmr Ford Trans Engr

Joined: Aug 1999

Posts: 24,712

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From: SE Florida

Quote:

Originally Posted by BC.7.3L

I've replaced my u joints and the problem remains. It's my understanding that u joints or drive shafts problems will occur at a certain rpm in any gear that you are in.

That's not my understanding at all. It also is not true. The u-joints do not know what the engine RPM is, they only know driveshaft RPM. It makes no sense at all that they would respond to engine RPM.

Since you have new u-joints I suspect your problem is in the alignment of the driveshaft. There has been some success fixing this problem by shimming the carrier so it moves down a little.

Quote:

Originally Posted by BC.7.3L

While down shifting the truck will coast, drop rpm, and then engage into the lower gear. Engine drag disappears for a second before it goes into gear.

That's how it works.

Quote:

Originally Posted by BC.7.3L

Also I've been told by several people not to let your tranny get up to 215 otherwise you'll cook it.

I've been told many things that are not true. You can add this to your list of things that are not true.

Jun 26, 2015 | 11:15 AM

BC.7.3L

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Thanks for the help! Do you or anyone else know of a good shop in Vancouver?

Jun 26, 2015 | 05:34 PM

Mark Kovalsky

Frmr Ford Trans Engr

Joined: Aug 1999

Posts: 24,712

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From: SE Florida

I don't know any shops in Vancouver.

Jun 27, 2015 | 12:54 PM

Brisco2

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When you say 215, Do you mean Celsius or Fahrenheit?

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Jun 27, 2015 | 04:42 PM

Vwags

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Joined: May 2014

Posts: 547

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From: Southern California

Quote:

Originally Posted by Mark Kovalsky

It has to be Fahrenheit. 215 Celsius is 419 Fahrenheit. That is WAY too hot!

You reminded me of a time I was smogging a Chevy Cavalier for a Nasa Engineer. The fan wasn't coming on and the temp was approaching the red. I shut it down and placed a fan in front of it and asked him if his fan ever comes on. Looking down his nose at me he told me he has "all the diagnostic equipment at home" and he "checked the whole system" himself. "The fan comes on at 200 C not F".

I just said ok and good by