Shop claiming transmission "clunk" is the differential

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Matticus

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I recently put a used transmission in my 2012 Expedition EL. The transmission came from a reputable place (LKQ) and had less than 50,000 miles on it. Not long after it was put in, I started to notice that there was an occasional "clunk" from the transmission as I was slowing down, right when the car would hit 25mph and shift into what I think is 3rd. Within a few months it was doing it more often and, sometimes, the noise was fairly loud and you could feel the car lurch slightly. While it will do this at any temp, it seems to do it much more as the transmission temp gets up 175 degrees or higher. It will happen when I am applying the brakes or just coasting down to 25mph. Otherwise, the transmission seems to work just fine.

The transmission is still under warranty from LKQ, but trying to get the shop I had install it to diagnose it properly has been ridiculous (story for another time). They are now saying they think it is a differential problem. That just doesn't seem logical to me - how could it be a diff problem when it happens so predictably at the exact same speed and coincides perfectly with the transmission shifting down to 3rd? Anyone have some insight?
 

stamp11127

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You may want to get a second opinion from a trans shop. Their scanner will record the shifting sequence so you can see what is happening internally when it cluks.
 

TobyU

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Check the u joints and rear half shafts for play too. Plus check trans mounts and motor mounts. Clunks can come from lots of places.
 
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1955moose

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Unfortunately, rebuilt transmissions are just that, rebuilt, not brand new. Replacing worn clutch plates and bands, is only half of a complicated rebuild like an automatic transmission. Their are so many other parts that get reused, that probably shouldn't. Have you ever really looked at a dealer shop manual for rebuilding a car/truck engine? Their are page after page of specifications that each part, or meshing parts must fall between as far as specifications. An automatic is even more so. Worn parts get reused all the time. Another thing I've seen happen is a shim or washer gets left out causing excessive play on a part. I remember my shop manager at the cab company I worked at back in 06, tell me, he had only one man that knew how to rebuild the crown Vic Transmission right. Unfortunately he left. All the others threw them together, but the installer had to sometimes pluck a fully remanned one, just to try another.
.


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stamp11127

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Moose, don't these millennials have 10 minute YouTube videos on rebuilding the trans? How hard can it be???
 

Adieu

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I recently put a used transmission in my 2012 Expedition EL. The transmission came from a reputable place (LKQ) and had less than 50,000 miles on it. Not long after it was put in, I started to notice that there was an occasional "clunk" from the transmission as I was slowing down, right when the car would hit 25mph and shift into what I think is 3rd. Within a few months it was doing it more often and, sometimes, the noise was fairly loud and you could feel the car lurch slightly. While it will do this at any temp, it seems to do it much more as the transmission temp gets up 175 degrees or higher. It will happen when I am applying the brakes or just coasting down to 25mph. Otherwise, the transmission seems to work just fine.

The transmission is still under warranty from LKQ, but trying to get the shop I had install it to diagnose it properly has been ridiculous (story for another time). They are now saying they think it is a differential problem. That just doesn't seem logical to me - how could it be a diff problem when it happens so predictably at the exact same speed and coincides perfectly with the transmission shifting down to 3rd? Anyone have some insight?

How much did you pay em for it?
 

1955moose

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Their was a show I was watching a few weeks back, joking about their son having a shirt he's wearing saying transmission expert. Expert at what, pulling them in/out, without breaking something. A used transmission with already 50,000 miles on it! I got a kick out of people that thought the used vehicles from Hertz rental were so great to buy used, because of the service schedule. What, they changed the oil and brakes? I worked for Hertz, and one of the perks of selling cars, was I got to drive one home each night, gas included. Let me tell you for a one year old vehicle, these cars were pretty iffy. I remember one Ford Taurus 1995, I think, that had such cheap front pads, that I lost total front brakes going down a 4 block grade here in Daly City. Takes a bit more than a 10 minute video to get a modern 6 speed trans to shift right. Maybe they'll train the robots that are driving the Beta Uber cars, to Rebuild Transmissions. Then they can have Shaggy put it in. Hopefully he'll remember the right fluid and quantity!

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Eswfarms

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Mine did a similar thing in my 2008, took it to dealer they reprogrammed the computer for the transmission and never had a problem since.
 
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Matticus

Matticus

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Sorry for taking so long to respond. For some reason, I didn't any of the usual notifications that I got responses.
How much did you pay em for it?
I think it was around $900. Came with a 1 year parts and labor warranty
 
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Matticus

Matticus

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Unfortunately, rebuilt transmissions are just that, rebuilt, not brand new. Replacing worn clutch plates and bands, is only half of a complicated rebuild like an automatic transmission. Their are so many other parts that get reused, that probably shouldn't. Have you ever really looked at a dealer shop manual for rebuilding a car/truck engine? Their are page after page of specifications that each part, or meshing parts must fall between as far as specifications. An automatic is even more so. Worn parts get reused all the time. Another thing I've seen happen is a shim or washer gets left out causing excessive play on a part. I remember my shop manager at the cab company I worked at back in 06, tell me, he had only one man that knew how to rebuild the crown Vic Transmission right. Unfortunately he left. All the others threw them together, but the installer had to sometimes pluck a fully remanned one, just to try another.
.
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This wasn't a rebuilt transmission


Their was a show I was watching a few weeks back, joking about their son having a shirt he's wearing saying transmission expert. Expert at what, pulling them in/out, without breaking something. A used transmission with already 50,000 miles on it! I got a kick out of people that thought the used vehicles from Hertz rental were so great to buy used, because of the service schedule. What, they changed the oil and brakes? I worked for Hertz, and one of the perks of selling cars, was I got to drive one home each night, gas included. Let me tell you for a one year old vehicle, these cars were pretty iffy. I remember one Ford Taurus 1995, I think, that had such cheap front pads, that I lost total front brakes going down a 4 block grade here in Daly City. Takes a bit more than a 10 minute video to get a modern 6 speed trans to shift right. Maybe they'll train the robots that are driving the Beta Uber cars, to Rebuild Transmissions. Then they can have Shaggy put it in. Hopefully he'll remember the right fluid and quantity!

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I'm confused.... are you saying that 50,000 miles on a transmission that is 6 years old is out of the ordinary?
 
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