Build thread - 3.08 to 3.42 front and rear gear change

DaveO9 said:

Awesome. Hot here this weekend, too, but probably not as hot. Worst time for me is late afternoon - sun dips down and shines into my west facing OH shop door. And I was working on the back of the rig this weekend.....

Got the rear end installed, all went in pretty easily. I'm to the point of mounting the rear wheels and install driveshaft and I'm done in back. Front, not so much. Finally got the old motor mount out today and the new one dropped into place with all but one bolt threaded in finger tight. I've had the most trouble with the front upper engine-to-mount bolt, both coming out and going in. I'll probably just have to bend the heat shield like I did to remove the old mount. After the mount is done, still have to
- remove and replace radiator/hoses
- run new Dorman oil cooler lines to new Denso radiator (new radiator has engine oil cooler, old one doesn't)
- Change oil and filter
- Install front carrier assembly
- change oil in front diff
- front driveshaft and axles
- hook everything up, etc. etc. View attachment 435081

@swathdiver or anyone else: do you know where this hanger goes? Pretty sure it came from the passenger side, but it's not showing up in any of my before pics. There's a similar longer one on the pass side for parking brake cable, so I think that's what it is, but I can't find where it goes.

Click to expand...

what (@swathdiver) he said...

It goes under driver side bump stop plate on the inside of the frame rail. You kind of have to get down and dirty there to see it as it threads in on the underside. It steers the brake cable onward and upward immediately after clearing axle tube, on its climb up to it's next point of contact along upper control arm.....

5StarCustmSolutns said:

Q: Dumb question: could you do a hummer mount on DS and stick with Tahoe OEM on Pass side? I'm not going to do this now, but something I've been thinking about if I DO have a failure on DS some day, or if I do some motor upgrades.

A: Yes, no problem. This is how my 2012 is currently.

More like a little high quality Q & A there!

Click to expand...

Honestly that maybe optimum!

When I had only the driver side H3 mount and stock passenger mount, I hadn't yet noticed any increase in vibration.
After installing the passenger side, I was certainly feeling more vibration.

I know everyone wants to replace parts as a balanced set (I do), but I think installing just driverside H3 mount will still reduce the torquing movement,
which should reduce the peak force that the weaker mount experiences due to less slack/movement.
Kind of like an engine torque strap chain, usually just installed on the lifting side?

So *I* think, a mixed set with one H3 mount, should outlast matched OEM liquid filled mounts.

BACK to AXN axle info.. Would I be good to order from LKQ online? I see one that is from a 2014 111k miles..
Many recyclers around me, but I haven't had great experiences going there..

SON of A GUN! @mikez71 I had three short paragraphs typed to answer you and tried to see where you live for final advise on LKQ vs local and lost it all....lesson learned

Two summers ago I was determined to sell GMT900 and get diesel. Looked at 1000's. Noticed trend: In pic from rear- left side was lower than right. Tail gate slanted down & left on vast majority. Brought it up at local engine builder shop. 5 guys there, 5 diff opinions. Called owner later, around midnight(he go bed at like 8pm lol) and said "I know what it is: Engine torquing on frame" Pretty sure he hung up on me. He called me back next day said I think you may be right? Makes for an interesting conversation, at a minimum

Only experience I have with motor mounts was on 2004 Acura TL. Was in Philly working. About 36yrs old and already knew EVERYTHING(not so) Developed thud on take off. Went to dealer, put on low lift, had me punch it and said it's motor mount. Well I knew it was transmission so I disputed. We traded places. He punched it. Me: WHOA WHOA WHOA! One side of engine jumped about 10" and slammed back down. IDK how it didn't break off? or hit hood? I need to replicate that with my truck now...

AXN: Self Source vs LKQ (or similar) = Time & Patience vs No Time & Money... If you live somewhere with larger car market or don't mind a drive to get one then self source it. I think I was as motivated by the core charge and amount they were selling the 10 bolts for than anything. $300 core charge at time. In essence they were charging me 300 to keep my 10 bolt, yet they were selling for $12-1400.. +$250 shipping... And selling 14 bolts for $5-750. At the time I thought they were taking these cores and slapping G80's in them to make $1000 each. I was looking at $800-1000 range to get a 14 and then shipping them my 10 bolt... Now I know that was giving them wayyyy too much credit. I don't think they don't get off the stool except for bathroom trips....or.....they certainly will not get off the stool and walk to the axle you're wanting to confirm it a 14 9.5... What computer says is what it is! Until you drive there and it's not.....twice

Self source wasn't easy but I learned a lot and scored a 14 bolt for $212 w/NO core charge, 3hrs away in Winston-Salem NC. Affording me the opportunity to put a $350 Yukon Posi or a $100 used G80 carrier in my old 10 and sell it for >$1000....or keep as backup? or use it for lawn furniture(current choice).....its shrink wrapped behind my garage
If you self source or anyone that reads this, I will, as long as I have cognitive ability, read back through my threads and convos with members to help you decipher the VIN yourself....so you don't have to try and get a junkyard dog off his stool

swathdiver said:

That one goes on the driver's side lower control arm bracket on the axle. It faces the differential housing. You'll see the threaded hole for it.

Click to expand...

Got it, thanks. Hanger bracket for both p-brake cables installed now and functional in the bracket for the LCA!

5StarCustmSolutns said:

I just woke up face down on my bench about 15min ago. So I apologize if I missed this but: Curious what the fluid looked like inside your 14 with 82k on it??

Click to expand...

All the oil had drained out of mine when I got it from LKQ, so I don't know.

Speaking of rear diff lube, mine's leaking. I used this gasket:


That shouldn't need RTV on either/both sides, correct? Goes on dry? I'm not sure why it's leaking. Best guess: When I was jacking the axle into place, the jack plate caught on the lip of the cover. I thought the tweak was just superficial, but now I'm wondering if it tweaked it just enough to make a poor seal between those two bolt holes. Remove and gently hammer flat? Can I reuse the gasket? What about just using RTV (Permatex Black) instead of or with the gasket?



In other news - DS motor mount is fully installed with all 7 bolts torqued down. Very pleased to have that part of the project done.

mikez71 said:

BACK to AXN axle info.. Would I be good to order from LKQ online? I see one that is from a 2014 111k miles..
Many recyclers around me, but I haven't had great experiences going there..

Click to expand...

Yes, I'd say go for it with LKQ Online. More info in my post #20 of this thread, but the big benefit with LKQ Online, at least for axles and carriers, is no core charge. So if you're upgrading to AXN, that's a big plus. When I tried to order from LKQ Portland, OR (20 miles from me) they quoted me a slightly cheaper price than online, but there was close to a $200 core charge. The other thing with LKQ online is find what you're looking for on the website, but then call the number during work hours to order. If you order online, you'll have to have it shipped to an address, which for me was $300 plus. But if you call, they'll transfer it to the LKQ will call closest to you for $50. I don't know if there's distance limit, but mine came from Idaho and CA - hundreds of miles away. Customer service on the phone is very good. You may have to wait for 15 minutes, but once you get someone they'll work with you till you're set up.

DaveO9 said:

Got it, thanks. Hanger bracket for both p-brake cables installed now and functional in the bracket for the LCA!



All the oil had drained out of mine when I got it from LKQ, so I don't know.

Speaking of rear diff lube, mine's leaking. I used this gasket:

More Information for GM GENUINE 26063649

That shouldn't need RTV on either/both sides, correct? Goes on dry? I'm not sure why it's leaking. Best guess: When I was jacking the axle into place, the jack plate caught on the lip of the cover. I thought the tweak was just superficial, but now I'm wondering if it tweaked it just enough to make a poor seal between those two bolt holes. Remove and gently hammer flat? Can I reuse the gasket? What about just using RTV (Permatex Black) instead of or with the gasket?

View attachment 435151

In other news - DS motor mount is fully installed with all 7 bolts torqued down. Very pleased to have that part of the project done.

Click to expand...

I've always used orange RTV on both sides, very thin, on paper gaskets like this. I ordered a Lube Locker off of Amazon, should be here in a few days. It's supposed to be reusable. My daughter came by and raided my spares!

Too bad nobody makes the rubber/metal one like the 10-bolts. Mine is still rockin' the original one.

DaveO9 said:

That shouldn't need RTV on either/both sides, correct? Goes on dry? I'm not sure why it's leaking. Best guess: When I was jacking the axle into place, the jack plate caught on the lip of the cover. I thought the tweak was just superficial, but now I'm wondering if it tweaked it just enough to make a poor seal between those two bolt holes. Remove and gently hammer flat? Can I reuse the gasket? What about just using RTV (Permatex Black) instead of or with the gasket?

swathdiver said:

I've always used orange RTV on both sides, very thin, on paper gaskets like this. I ordered a Lube Locker off of Amazon, should be here in a few days. It's supposed to be reusable. My daughter came by and raided my spares!

Too bad nobody makes the rubber/metal one like the 10-bolts. Mine is still rockin' the original one.

Click to expand...

Click to expand...

Originally cheaped it, bought an $8 paper gasket. Looked at it for a couple weeks. Picked it up a couple times. Dropped it once, and gasped because I thought it was going to be damaged. Even made a protective case, a giant envelope of cardboard and painters tape to protect it.....then one day I thought this is way too big of a project to not go all the way! And ordered the $30 Lube Locker!
Where I once worried about creasing or fraying the fibers of the frail paper gasket.....We were now using the Lube Locker as a frisbee during lunch and as a pillow for mid day siesta's! ;-)

@swathdiver or @5StarCustmSolutns: could either of you send me an Amazon link for the lube locker gasket? I am not finding it there or on RA. Thanks!

DaveO9 said:

@swathdiver or @5StarCustmSolutns: could either of you send me an Amazon link for the lube locker gasket? I am not finding it there or on RA. Thanks!

Click to expand...

Got mine from Summit, but could've been in big order and free shipping?


Quick Perf shows free ship to WV in case Summit hitting over the head for ship??


edit: Did not see on Amazon, went through all 7 pages of LL gaskets

5StarCustmSolutns said:

Got mine from Summit, but could've been in big order and free shipping?

LubeLocker LLR-G14SF LubeLocker Differential Cover Gaskets | Summit Racing

Free Shipping - LubeLocker Differential Cover Gaskets with qualifying orders of $109. Shop Differential Cover Gaskets at Summit Racing.

www.summitracing.com

Quick Perf shows free ship to WV in case Summit hitting over the head for ship??

LLR-G14SF-GM 9.5" / 14 Bolt Semi-Float / LubeLocker / P

www.quickperformance.com

edit: Did not see on Amazon, went through all 7 pages of LL gaskets

Click to expand...

thanks, on order from quickperf!