How hard is it to swap my 3.08 gears to 3.73 gears?

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Ewhitaker0020

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They were not installed at the same time. I have an Escalade LS 6.0 and 4L65E in there now. No comparison to a 305.
If you go 8 lug, you should be able to find 4.10 from the factory. I believe 3.73 was the largest from factory in 6 lug, 1/2 ton form.

When you say go 8 lug, do you mean I would switch to 3/4 ton axles?
 

mcarlo86

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Yessir. Without hesitation.
4.10 is not enough either. ;) lolo

Need more speed /lower E.T. / run a smaller diameter tire.
Need more mph /top end / run a taller tire.

But listen to Craig , im a jackass. He's way more "moderate" than I am, just ask @Tom Sawyer
If i had the choice, 4.56 is the git r dun :grd: gear for damn near everything but Iike to drag race.

Ive said that before. 4.56 or bust.

If you gotta go 4.88 youre trying too hard.

I like your thinking @Rusty Nail. Driveability is always better when you are operating in the peak torque range. Small blocks like to spin, so I say spin them!
 

Octane

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Personally I'd rather just change to a 350 and forget the gear hassle.305 is a slug anyway.I had two chevy vans once,one with a 350 and other was a 305.That 350 would out pull,out run and outclimb on every hill.Same size vans and same gears.
 

Ricko1966

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I'm ready for more blather.
 

Ewhitaker0020

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Personally I'd rather just change to a 350 and forget the gear hassle.305 is a slug anyway.I had two chevy vans once,one with a 350 and other was a 305.That 350 would out pull,out run and outclimb on every hill.Same size vans and same gears.

Wouldn't a 350 with 4.11 gears be an even better combination though? I can't afford the engine swap now, but I can probably afford the gear change to get me through to the engine swap and then I'll have both done.
 

mcarlo86

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Wouldn't a 350 with 4.11 gears be an even better combination though? I can't afford the engine swap now, but I can probably afford the gear change to get me through to the engine swap and then I'll have both done.

You are correct. I'd do the gear change which will be worth it for the mean time and then save up for a good 350 swap to complete the deal.
 

Ewhitaker0020

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You are correct. I'd do the gear change which will be worth it for the mean time and then save up for a good 350 swap to complete the deal.

That's what I was thinking. Now the hard part might be finding gears. Then again I know 1 guy local who just might be able to help me out.
 

RoryH19

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When you say go 8 lug, do you mean I would switch to 3/4 ton axles?
Right, 3/4 ton axles. 1 tons also have 8 lug but that would typically be a Dana 60 up front and a full float 14 bolt in the rear.
 

Ricko1966

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Wtf does that mean anyways?
Reckon Tom's from California or something?
Oregon maybe.

https://www.dictionary.com/browse/blather?s=t

Hrm.

:blah:

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I really am not sure what it's supposed to mean, but I probably need to figure it out.That way I can accurately tell which threads have sufficient amounts of blather vs. not enough or too much.Gut feeling was there wasn't enough blather on this one.Thus the request for more blather.
 

Rusty Nail

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Maybe I can help.
A little.

Certainly cant be in the mood to write an hour long blather-fest EVERYDAY.
I gotta eat.
:D
And write reports....:angry94:
Its Sunday. well, 0031 Monday now and my work week ends at 0600.

Im really very tired.
It started getting hot and I shot my load yesterday morning about 0636 when I finally caught up to the badguy i've been hunting and chasing after since December 14th.

Remember last week?
I was so close he dropped his dope ?
:mad:
Grr
Well he ran out of luck and I ran out of patience - Poor BG had warrants and now he's on his way back to prison.
I really like this slow time waiting on the next gig though but the pressure in here is THICK man.
LoLoLo

Maybe he'll stay clean this time. :shrug:

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Ricko1966

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Got it! So blather isn't just exhausting, it makes you hungry also.So my new plan, 1 take a nap. 2. eat a good meal and arm myself with a snack. 3. Check for blather. Did I miss anything?
 

Octane

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Wouldn't a 350 with 4.11 gears be an even better combination though? I can't afford the engine swap now, but I can probably afford the gear change to get me through to the engine swap and then I'll have both done.
Maybe so.I have 3.73's and a 350 in a fulltime k10 and it does pretty good. I've had an overload of 2 tons in the back and it pulled it.Too much for a 1/2 ton to haul.I'm sure I'd lose too much fuel economy for my liking with 4:10's but if you need it, you need it I guess.
 

Craig 85

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How well did you like the 4.10's? I'll probably be going with 31's just so I don't have to worry about any fitment issues.

4.10's really picked up the bottom end. My truck was a Calif smogged 150HP 350. An overdrive would have really helped though. The truck didn't have too much more to give after about 3500 RPM.
 

Bextreme04

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I've got a 1980 K25 with 350/TH400/NP205, 4.10's and 35's. It is barely noticeable when I have 2 yards of 3/4" minus in the bed(~4,000lbs)... it accelerates fine up to highway speed just a little slower than with an empty load. I've also pulled a 5,000lb travel trailer over the cascades to go elk hunting at 65mph with no issues. I had a C20 with 4.56's also and it was definitely more peppy, but it was wound out and screaming by about 60mph. I think you would be very happy with a 350 swap and 4.10's... it would certainly be a huge improvement over the 305 and 3.08 gears.

I think my motor has at least a cam in it though, it's probably not fully stock. It for sure has roller rockers and has a lumpy idle, so I'm thinking some PO put a cam in it to pep it up a bit. 350's are so plentiful that they seem to be available for pretty cheap in my area. I'm probably going to sell my engine and trans in the next month or so when I am ready to do my swap. I'm assuming i'll get ~$500 for the engine and the same for the trans. I'll list it higher and see what I get. It helps that it is a running, driving combo now so people can verify that it is good before buying. L29 MPFI 454 parts should all be ready to come back from the machine shop this week and I just need to order the rebuild kit and put it together now.

I also see rolling chassis for sale in my area pretty regularly for a few hundred dollars. You should be able to buy a rolling 3/4 ton chassis for $300-500 dollars, take the front and rear drivetrain out and sell the rest.
 

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