ITGuy's 2003 Sierra 1500/2500 4x4 RCLB Build Thread

I think you may be right? It could have been special ordered. My donor was a cab and chassis.. who knows. I read that GM used to produce it [3.73 and 4.10/11] with the gas versions.
Quick way to tell is cracking open the glove box and find the G codes. If one is GT4 then it's 3.73. If it says GT5 then it is 4.10/11

I was going to spin the wheel and count DS rotation... either way I'll know tonight.
 
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You will like the performance and mpg gain from going to 4.10 with the larger tires and wheels, but at the same time it's not totally necessary. It would get you back to a stock tire size performance however. The good news is the 11.5 axle uses threaded adjusters, so it's not too bad to change out the ring and pinion, not as involved as say doing a 10 bolt 8.6 rear axle
 
a-fuso said:
You will like the performance and mpg gain from going to 4.10 with the larger tires and wheels, but at the same time it's not totally necessary. It would get you back to a stock tire size performance however. The good news is the 11.5 axle uses threaded adjusters, so it's not too bad to change out the ring and pinion, not as involved as say doing a 10 bolt 8.6 rear axle
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What about jumping up to a 4.56? I could return my current set and get the front and rear, especially now that I am turning larger rims and tires.

Looks like I need to get that efi live in sooner than later. Just the change in the rims and tires have cut into the performance. The LBZ still pushes them along nicely, but won't snap your head back.

Think I should go that route before re-gearing? Not a big deal.. and I will probably end up doing both in the end. I'm presently looking for a better garage to store my stuff and work on my trucks. It's slowing down my build.
 
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I would ask @Cornell What he recommends, If I remember right he was saying 4.10 is better with 35s and 4.56 with like 37-38s

I've read before that turbo and supercharged vehicles need a little less gearing than N/A because they need some resistance to pull against.
 
a-fuso said:
I would ask @Cornell What he recommends, If I remember right he was saying 4.10 is better with 35s and 4.56 with like 37-38s

I've read before that turbo and supercharged vehicles need a little less gearing than N/A because they need some resistance to pull against.
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For the LBZ on 37s I wouldn't do 4:56's but its up to you, super overkill IMO.
 
Ordered

BT DieselWorks - Gauge pod mount digital DSP-5 Switch & Pre-crimped Duramax ECM pin with wire - Link
maxresdefault_zpsklkciec8.jpg
 
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It's actually taking me longer to pick out a gauge pod.. primarily because I don't like any of them! Thanks for the tip though.
I hope to have the rest of the stuff ordered today! Still deciding on digital gauges vs. a new monitoring system.
 
Yeah they have nice pillar mounts. If I do a pillar, I'd get a 3 pod and use 1 for the DSP5 Switch I ordered.
The others could be boost + egt temp or something helpful.

The other route is something like an EDGE Insight CTS2 monitor.

And of course then the is the "I have more money then I know what to do with solution" - Autometer Custom LED gauges
:hng:
 
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