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

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iamdub

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Survey says..... ????

Well, the original mounts were blown since before I bought it 46,000 miles ago so I've always had to be gentle when accelerating. For the first time ever, I can now thoughtlessly jab the throttle to shoot a gap or accelerate to merge with traffic. That "thud" I've gotten so used to hearing and feeling is gone. It's actually gonna take some time to get used to. I even tried a couple hard launches from a stop and I'm so programmed to ease into the throttle that it was like I picked up 100 ft-lbs of torque off idle! As far as vibes at idle, they may be lesser. They're certainly not worse. Absolutely glad I did it, not that I ever had any doubts. Anything would be better than what I had. The play in the original LH mount was the equivalent of to links in a tow chain, the RH mount was "just" split/cracked. The original transmission mount was probably fine, but was almost an inch shorter than the new one. Either it was a little shorter to begin with or it had squashed that much. For it's minimal cost, I'd rather replace it than not.
 

Rocket Man

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Well, the original mounts were blown since before I bought it 46,000 miles ago so I've always had to be gentle when accelerating. For the first time ever, I can now thoughtlessly jab the throttle to shoot a gap or accelerate to merge with traffic. That "thud" I've gotten so used to hearing and feeling is gone. It's actually gonna take some time to get used to. I even tried a couple hard launches from a stop and I'm so programmed to ease into the throttle that it was like I picked up 100 ft-lbs of torque off idle! As far as vibes at idle, they may be lesser. They're certainly not worse. Absolutely glad I did it, not that I ever had any doubts. Anything would be better than what I had. The play in the original LH mount was the equivalent of to links in a tow chain, the RH mount was "just" split/cracked. The original transmission mount was probably fine, but was almost an inch shorter than the new one. Either it was a little shorter to begin with or it had squashed that much. For it's minimal cost, I'd rather replace it than not.
Damn, I didn’t realize you’d been running on broken mounts that long. I bet it sure does feel good to finally mash the throttle, now you just need to get used to it.
 

iamdub

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how difficult was that?


LH (driver's) side was a mother-effin' BREEZE compared to the RH side. I had maybe an hour invested into it. All I had to remove on that side was the section of the steering shaft that comes out with some 15mm bolts.

The RH side was a nagging *****. A/C lines, heater hoses and the starter all were in the way. I had to remove the heat shield on the manifold to have access to the mount bolts. Then unbolt the knock sensor and remove the starter to have JUST enough clearance to get the mount out, turning it all different ways to finagle it out of there. I didn't completely remove the starter, just let it hang in place near the bellhousing. I covered the power terminals with a shop rag to avoid a fireworks show. After I unbolted the mount, I had to rotate it to remove the two nuts that hold the engine side plate to it and take the mount out in two pieces. You can't rotate it all the way around, so you're doing it by Braille and a fine-toothed ratchet is a savior here. The only route to work it is through the wheel well. The H3 mount can't be taken apart, but it's smaller so getting it into position was a matter of rotating it all around to slip it between the A/C line near the firewall (which has a heat shield), the frame, and whatever else is crammed in that area.

I used varying combinations of short and deep 15mm sockets, "wobble" extensions, U-joint adapter, and short and long extensions. All 3/8" drive because none of the bolts require any significant torque. I consider myself very fortunate to not have rust as a factor!
 

iamdub

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Damn, I didn’t realize you’d been running on broken mounts that long. I bet it sure does feel good to finally mash the throttle, now you just need to get used to it.

About half of those miles were put on by Jenn when she daily'ed it for about a year. If it had been me, I probably would've worn through the metal U-bolt inside the mount and had total separation!

It really is a weird feeling! My mind tells my right foot to "stomp it", but my foot is still like "give it 15%, then ease into WOT".
 

shreksbrother

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Installed H3 motor mounts and stock transmission mount.
Just did my driver side. Other than breaking the torque on the three frame side bolts, I did the entire project from under the truck. I didn't remove the steering column, wheel, or fender liner.

The old mount was definitely toast. My clunk is gone, as well. Unfortunately my idle isn't as smooth as I would like it to be, but it's better feeling.9c20c2a09a55ddfddb1f16ab9058da22.jpg

Sent from my Galaxy Note9 using Tapatalk
 

PG01

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Well, the original mounts were blown since before I bought it 46,000 miles ago so I've always had to be gentle when accelerating. For the first time ever, I can now thoughtlessly jab the throttle to shoot a gap or accelerate to merge with traffic. That "thud" I've gotten so used to hearing and feeling is gone. It's actually gonna take some time to get used to. I even tried a couple hard launches from a stop and I'm so programmed to ease into the throttle that it was like I picked up 100 ft-lbs of torque off idle! As far as vibes at idle, they may be lesser. They're certainly not worse. Absolutely glad I did it, not that I ever had any doubts. Anything would be better than what I had. The play in the original LH mount was the equivalent of to links in a tow chain, the RH mount was "just" split/cracked. The original transmission mount was probably fine, but was almost an inch shorter than the new one. Either it was a little shorter to begin with or it had squashed that much. For it's minimal cost, I'd rather replace it than not.
Wait, i felt like i got more throttle response from my ‘eye-talian throttle mod’ by moving my gas pedal 1/4” but you picked up 100 torques from a new motor mount?

Lmfao.....

The ‘Louisiana motor mount mod’.......LMMM.......

;)
 

iamdub

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Wait, i felt like i got more throttle response from my ‘eye-talian throttle mod’ by moving my gas pedal 1/4” but you picked up 100 torques from a new motor mount?

Lmfao.....

The ‘Louisiana motor mount mod’.......LMMM.......

;)

Hold up, swolled up! I said it was LIKE I picked up 100 ft.-lbs. IIRC, you insinuated with your "mod" that your throttle response actually did improve, which was grounds for ribbing you.
 

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