H55 Over-run "Humm"

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Update: it's still pouring here..naturally

I went to the transmission shop today, and had them assess the transmission.

The consensus was it's an input shaft bearing. Which leaves me wondering why it would fail at 30k miles and How involved is it to replace that bearing on my own? Or am I better off finding a decent place to replace it for me given the fact that I don't have a garage at the moment?
 
EasternYeti said:
Update: it's still pouring here..naturally

I went to the transmission shop today, and had them assess the transmission.

The consensus was it's an input shaft bearing. Which leaves me wondering why it would fail at 30k miles and How involved is it to replace that bearing on my own? Or am I better off finding a decent place to replace it for me given the fact that I don't have a garage at the moment?
Click to expand...

IIRC to replace the input bearing you basically have to tear it all apart and serious pullers are required. Find a reputable shop to handle it.
 
Output Shaft said:
New h55s don't blow up their front bearings.

What happens when the truck is idling & you push in the clutch? Any weird sounds?
Click to expand...

No sounds when the clutch is engaged at idle, and little to no noticeable change when clutching in gear while the sound is occurring

Trying to comprehend how a H55 could blow a bearing that quick, as I'd like to make sure it doesn't happen again
 
Who installed it?
It's possible that the input shaft got cram fit into the pilot bearing during installation resulting in excessive axial force pressing it rewards on the front bearing. We also don't know if it was installed without a mishap. It's really easy to tweak the front bearing alignment if the transmission suddenly dropped or lurched while the input shaft tip was still inserted in the pilot bearing.
Of course if the guy who installed it was asked about anything, he'd deny everything, but I'd venture to guess that there was absolutely nothing wrong with the transmission when it was unboxed new.

Of course it may very well not be installer error... but it definitely could be too.
 
Output Shaft said:
Who installed it?
It's possible that the input shaft got cram fit into the pilot bearing during installation resulting in excessive axial force pressing it rewards on the front bearing. We also don't know if it was installed without a mishap. It's really easy to tweak the front bearing alignment if the transmission suddenly dropped or lurched while the input shaft tip was still inserted in the pilot bearing.
Of course if the guy who installed it was asked about anything, he'd deny everything, but I'd venture to guess that there was absolutely nothing wrong with the transmission when it was unboxed new.

Of course it may very well not be installer error... but it definitely could be too.
Click to expand...

This is a good point to mention, the P.O was pretty meticulous. If it was an issue that occurred during the install he likely didn't realize it occurred.

One thing I can say that he was very clear about the lingering (?) he had with the truck before he sold it, one of the best things about this community is how up front we all are with one another.

Heeding everyone's advice on here I'll likely go with what Godwin suggested. The shop will stand by their work, and I'll have that assurance moving forward. As hesitant as I am to have the truck in someone else's hands for the first time, it's the smartest decision I can make until I have a shop again
 
There is a H55F specific FSM but I don't have access to it right now or I'd post the number for it. If you do not have a shop experienced with the H55F rebuild the tranny you may want to track down a copy of the FSM that they may use.
 
Godwin said:
There is a H55F specific FSM but I don't have access to it right now or I'd post the number for it. If you do not have a shop experienced with the H55F rebuild the tranny you may want to track down a copy of the FSM that they may use.
Click to expand...

In anticipation of that issue I had this manual printed and bound today, it's the right one correct?

For those in need this is the H55 FSM link. Only cost me 5 bucks to have it bound and printed
http://www.serie4.it/download/h41-h42-h50-h55f.pdf


IMG_0636.webp
 
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