GMT900 owners: OE motor mount upgrade

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I ran into said issue again this afternoon, and while it may have been mentioned previously on this board I believe it bears repeating.

For those that don't know, the '07-'13 GMT900 trucks are notorious for repeat LH engine mount failures. The original fluid-filled mounts are woefully inadequate at wrangling even the wheeziest of LS engines. Luckily, there's an economical and OEM-sourced solution: GM part # 25847739.

Said part # references an OEM, fully solid engine mount used in the Hummer H2 Alpha. Not only does it not suffer from the original failure points, it's a direct bolt-in replacement for any GMT900 platform and incorporates a much smaller heat shield which makes installation much easier.

Anyone with a GMT900 truck should seriously consider this part should they find themselves in need of a replacement.
 
I replaced both on our 07 Yukon Denali w/6.2L (174k miles) last April and a whole lot more:
Changed all 4 O2 sensors, two # 213-3533 & two # 213-3538
Changed knock sensors, two# 213-1576
Changed both differential mount brackets, GM# 23104735 & 6
Changed both motor mounts (2), GM# 25847739, $100 each
Changed tranny mount, GM# 15840278
Changed trans pan ATF (6 qts) ACDelco Dexron6 #10-9395, $39
Changed trans filter GM# 24236933, $26
 
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It's a good solution that I've used many times, You just need to careful with you're more discerning clientele....Especially with active AFM . The Hummer mount transmits frequencies that the fluid filled mounts cancel out.
 
It's a good solution that I've used many times, You just need to careful with you're more discerning clientele....Especially with active AFM . The Hummer mount transmits frequencies that the fluid filled mounts cancel out.

Definitely a good point. The truck in question belongs to the FIL of one of my service advisors. Said advisor explained the differences and possible side effects, and he was more than fine with that in exchange for a longer lasting part (the owner is an engineer, so he gets it).
 
I've replaced probably 100 of these and have used aftermarket fluid filled mounts with no issues....I wont use a solid mount because vibrations will result.
 
My original mount in my 900 lasted 120k. Replaced with OEM. None of the geometry has changed in yours has it? But then again, I had the 4.8 without the AFM. Maybe the 5.3 AFM had different mounts? Mine didnt seem fluid filled (from what I could tell).
 
I went the other direction--from the conventional rubber mount that had failed on my 08 Silverado 4.8 to a fluid filled/hydraulic mount that smoothed out the vibrations felt through the vehicle. Suppose I'll see how long they last.
 
To follow up: I installed the solid mount this past Monday, and the truck drive amazing. There's absolutely no vibrations at any engine speed.
 
It's the LC9 5.3 with a 6L80E. I had the AFM turned off in the computer around 150k miles.
I know one guy with the same thing in a 2010. He has around 290k miles. Never had AFM turned off or anything like that. All original drivetrain and no lifter failures. It does burn some oil but it still runs good even after being run low on oil a few times.
 
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