Growing up doesn't have to suck

Bigbeardenali1992 said:

How come the H3 mounts are so much beefier looking?! I would think that a tahoe or burb being a bigger truck would already those beefier motor mounts given that’s a bigger truck with a bigger motor? Why does the H3 have bigger?

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@Bigbeardenali1992 Chase, just want to make sure you know stock in @iamdub pic is on the left and new h3 is on the right.

Okay, a little more research answered my question but caused another. In 2008 the H3 came with the "Alpha" option and a 5.3L V8. GM shows part numbers for mounts are 25847738 for left & 25847739 for right.

iamdub said:

Just finished installing those H3 mounts and stock trans mount. The driver side was an effin' BREEZE compared to the passenger side. Gonna clean up then take 'er for a victory lap.

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Hey iamdub, do you happen to have the part numbers for those H3 motor mounts handy? I'm usually pretty resourceful but I struck out with a search of the forum...or rather the forum struck out with no results for "H3 mounts" other than in your thread. I checked GMpartsdirect and the diagram of the H3 mounts don't look like the pic of the mounts in your thread...the H2 mount diagram looks closer, but you didn't say anything about H2. Help/clarification is appreciated!

ls1yukon said:

Okay, a little more research answered my question but caused another. In 2008 the H3 came with the "Alpha" option and a 5.3L V8. GM shows part numbers for mounts are 25847738 for left & 25847739 for right.


Hey iamdub, do you happen to have the part numbers for those H3 motor mounts handy? I'm usually pretty resourceful but I struck out with a search of the forum...or rather the forum struck out with no results for "H3 mounts" other than in your thread. I checked GMpartsdirect and the diagram of the H3 mounts don't look like the pic of the mounts in your thread...the H2 mount diagram looks closer, but you didn't say anything about H2. Help/clarification is appreciated!

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Your link to the H3 mount is for a 2006 which doesn't have the 5.3l in it. That is why it doesn't look right.

25847739 is the one you need.

It is the passenger side mount for the '08-'10 "Alpha" (5.3l) H3 but it fits both sides of our trucks.

Thanks for the follow up...I found what you're talking about but you probably replied and I didn't refresh the page before editing my post. Good to know that 25847739 fits both sides...it's the cheaper of the two.

Ken got ya handled. When I was price shopping, most places had the V8 H3 (2010, I think) listed as the "Championship Edition". But, yeah, the passenger side mount for the H3 is the one (or two) you need for one or both sides of our vehicles.

So how are you liking the mounts Chris? Driven the Tahoe much since the repair?

swathdiver said:

So how are you liking the mounts Chris? Driven the Tahoe much since the repair?

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I've only driven a couple hundred miles but I'm loving them! I had gotten so used to babying the throttle and hearing and feeling that clunk every time I drove it. I still haven't gotten used to the way it feels now- I'm almost missing the clunk and kinda feel like something is wrong just from the familiarity! As far as transmitted vibrations, I don't feel any more than before and I'd venture to say there are actually less now. So glad to have finally moved forward from that chapter and looking forward to the next round of repairs and upgrades!

iamdub said:

I've only driven a couple hundred miles but I'm loving them! I had gotten so used to babying the throttle and hearing and feeling that clunk every time I drove it. I still haven't gotten used to the way it feels now- I'm almost missing the clunk and kinda feel like something is wrong just from the familiarity! As far as transmitted vibrations, I don't feel any more than before and I'd venture to say there are actually less now. So glad to have finally moved forward from that chapter and looking forward to the next round of repairs and upgrades!

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So would you say the same or less vibration than when the originals were intact and working properly? When the day comes that mine needs new ones, I've been of mind to keep the originals but not if there's no downside to these solid rubber mounts.

swathdiver said:

So would you say the same or less vibration than when the originals were intact and working properly? When the day comes that mine needs new ones, I've been of mind to keep the originals but not if there's no downside to these solid rubber mounts.

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I bought my Tahoe 47,000 miles ago with around 146,000 on the clock. I don't know when I officially "tested" the mounts, but it wasn't long after I bought it and they were shot then. The port side was blown because I noticed the dried rust-colored trails originating from the mount while underneath for it's first oil change under my ownership. The starboard side leaked soon after because the rust-colored fluid was fresh and wet. So, I can't say how the original mounts feel in comparison. My Tahoe sometimes idles so smoothly that I can barely tell it's running and other times it has what feels like a very slight random misfire. I haven't been able to relate the varying idle characteristics to any particular type of driving, atmospheric conditions, fuel brand and grade, etc. I'm not so concerned with it as, apparently, it's completely normal for these things. I'd say that, with the H3 mounts, it seems to have the "smooth idle" spells more often. By the way, when I mention the idle vibes, I don't mean anywhere near how poly engine mounts feel. The vibes I'm referencing are strictly those infrequent "pulses" that feel like a slight random misfire, like once or twice within a 5-10 second period.

I honestly see NO downside to the H3 mounts. The hydraulic mount is a weak design and I really think was only conjured up to help absorb the extra vibrations that occur when AFM is active. My AFM has been disabled for about a year now so I surely don't need the special (and weak) mounts. Even if my AFM was still active and even if the H3 mounts transmitted noticeably more vibrations, it couldn't be much and surely not enough to warrant electing to repeatedly replace the hydraulic mounts after every time the truck towed or was driven more spiritedly (such as when your wife drives).

It's definitely a job I'd only wanna do once if I could help it. I'd rather have the small chance of feeling a shake ever so often than the guaranteed chance of having to repeat their replacement.

iamdub said:

...it couldn't be much and surely not enough to warrant electing to repeatedly replace the hydraulic mounts after every time the truck towed or was driven more spiritedly (such as when your wife drives).

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LOL