What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Just Fishing

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So main bearings or was it just thrust bearings? I thought you replaced them and were all set. Sorry but my email notifications keep quitting and I end up falling behind in my followed threads. Stupid TYF web service.

yeah i did just the thrust bearing and it burned it out again.
since then i also bypassed the trans oil coolers after attempting to get a before and after pressure reading.
Was never able to confirm for sure due to a short oil pressure gauge hose, but i did notice i'm getting more transmission/engine breaking with the coolers bypassed.

I also was able to reverse flush some metal from the transmission cooler when i disconnected it, so i'm feeling pretty good that it's the issue...

I left it there, decided i was done and needed to get outside and do things for the remaining part of the summer.

getting back to it now, plan is to pull the pan and see if the crank looks ok, or if i see more damage than last time.

Plan is to roll a new (probably the original used 5.3 thrust i have) thrust bearing in to place to see if it burns it out.

If it looks good, then i'll roll a fresh bearing into place and run it.


If the engine gets pulled, i'm installing a transmission pressure gauge (probably a perm install like i did to my vette).
Transmission pump will probably get replaced for good measure.
and all new bearings, and possibly new crank.

I'm hoping i don't need to go that far.

:yuno:
 
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iamdub

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yeah i did just the thrust bearing and it burned it out again.
since then i also bypassed the trans oil coolers after attempting to get a before and after pressure reading.
Was never able to confirm for sure due to a short oil pressure gauge hose, but i did notice i'm getting more transmission/engine breaking with the coolers bypassed.

I also was able to reverse flush some metal from the transmission cooler when i disconnected it, so i'm feeling pretty good that it's the issue...

I left it there, decided i was done and needed to get outside and do things for the remaining part of the summer.

getting back to it now, plan is to pull the pan and see if the crank looks ok, or if i see more damage than last time.

Plan is to roll a new (probably the original used 5.3 thrust i have) thrust bearing in to place to see if it burns it out.

If it looks good, then i'll roll a fresh bearing into place and run it.


If the engine gets pulled, i'm installing a transmission pressure gauge (probably a perm install like i did to my vette).
Transmission pump will probably get replaced for good measure.
and all new bearings, and possibly new crank.

I'm hoping i don't need to go that far.

:yuno:

Did you measure the crank snout depth when you installed the pulley?

img_1020-jpg.jpg
 

George B

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Got a P015B code and CEL this morning. Tech2 called out B1S1. Exhaust got stinky too. I did a graph of the sensors and they seem to sweep ok. Fuel trims are ok with LTFT -3 on both banks. I will take a look at that sensor since I was just working in that area the other day. Might be time for a pair of new sensors at 88K...
Should I bother with the genuine GM sensors or just go for the Denso units on RA? I recall reading that Denso made them for GM anyway.
 

George B

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George B

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