Gears Done... Finally!

Well I finally got the front and rear gears done. A buddy of mine from work helped with the rear install and setup. He got me all schooled up on the basics, and really it's not as bad as I thought it was going to be. We spend a solid 8-9 hours in my garage going through the rear. We pulled every bearing, bearing race, seal, and rebuilt this thing from end to end. The front on the other hand had me all confused. But... Gasguzzler chimed in and next thing I knew the front was also rebuilt from end to end. I ended up doing 4.88's with a Detroit True Trac and installed a Mag-Hytec diff cover for the rear.

Special thanks to Gasguzzler for installing and setting up the front diff for me, your a life saver man!

And another special thanks to Cowl327 for hooking up the tuning, and updating it for the new gears.

Soo tell us what improvement you noticed and how much. I want to go to 4.88 but i still want it to cruse nice down the high way.

Honestly, I haven't really had much drive time in it yet.

With the 35's and the 4L60 it looks like it's turning around 1900-2000 RPM's at 60 MPH. I gave her just about half throttle from a roll, and she pulls pretty good. They feel really good, and it's hard for me to keep my foot out of it, till the gears break in anyway. Then I'll really tell ya how they feel!

I'm digging up a gear/tire size calculator now to compare the speeds and RPMs.

If your running 35's now I'd recommend 4.88's. Some many people I talked with that had 35's and 4.56's said they would do 4.88's if they had it to do again. I believe it's like 150-200 RPM difference between the 4.56's and 4.88's.

Good deal. Wait 'til the fuse burns in the front diff....

LOL, just messin' (if something weird happens call me 1st). :LOL:

How'd the rear yoke swap go?

Oh, nevermind, I'll see you tomorrow. :lol:

Badass man! Didnt you used to have 4.56s?

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Originally Posted by Aggie

Badass man! Didnt you used to have 4.56s?

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No, I was sporting the 3.73's with G80.

MAN! what a great running and looking truck!Its gotta be the best looking truck ive seen and the new parts make it even better.Your welcome buddy! anytime...

I have to agree with Dale. The truck is beautiful, and runs like a raped ape given the fact that it is stock with a tune. I'm not gonna lie, I almost had to change my pants after he stomped into it and I wasn't paying attention.

Yeeee Haaawwww!

:woot:

What oil did you use? Should be doing mine next week

what is the rpm at 70 mph? i am having 4.56's put in mine and probably a 37" tire. ill be getting the same diff covers also. i got the tranny pan which holds an extra 4.5 quarts already, they make some really nice covers. i dont know how well they would do being bashed on rocks compared to a steel cover but they are definitely quality.

do 4.88 for a 37

any updates on the dd-ing.

Yes, from what Steve and I talked about do the 88's. I think he's at 35" and loves the 88 he/we/they put in.

What kind of oil/additive is recommended? I like that diff cover, I'm going to have to look into getting one

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Originally Posted by 567234ta

what is the rpm at 70 mph? i am having 4.56's put in mine and probably a 37" tire. ill be getting the same diff covers also. i got the tranny pan which holds an extra 4.5 quarts already, they make some really nice covers. i dont know how well they would do being bashed on rocks compared to a steel cover but they are definitely quality.

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Definitely go with the 4.88's, after hearing how Steve's truck acts with the 4.88's and 35's, that is the route I would go especially with 37's. I'm just waiting for the money fairy to visit me so I can put them in mine. He keeps visiting Steve instead of me apparently.

well ive already got the 4.56's just not installed yet. with a 37" it should make it pretty close to stock rpms.

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Originally Posted by MKader17

What oil did you use? Should be doing mine next week

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I'm running Mobil 1 75 90 front and rear for break in purposes, after 1500-2000 miles I'll switch to maybe Lucas or something. The front called for 80-90 sythetic and the rear called for a 75-90 sythetic. I'm one of those guys who likes to use what GM recommends, but they want 34-35 dollars a quart for the Delco synthetic 75-90 for the rear, and 8 or so bucks for the 80-90 synthetic for the front. I can deal with the front stuff, but seriously 34-35 bucks a quart before taxes! They can keep that stuff, and when it goes on sale I'll pick some up.... So I'll break them in with the 75-90 Mobil 1 and go from there.

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Originally Posted by 567234ta

what is the rpm at 70 mph? i am having 4.56's put in mine and probably a 37" tire. ill be getting the same diff covers also. i got the tranny pan which holds an extra 4.5 quarts already, they make some really nice covers. i dont know how well they would do being bashed on rocks compared to a steel cover but they are definitely quality.

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At 70mph with my 35's and the 4.88's I'm pushing mid 2300 to 2400 rpms. Typically 65 mph is what I cruise on the highway and I do that at about 2100-2200 rpms, but I don't think 70 mph at those rpm's is too bad. She has tons of torque now with this gear set, no downshifting up steep grades, she just pulls right along. I can't wait to she how she does with a trailer behind it. My main reasons going with the 4.88's was lots of guys I talked with that rans 35's and had gears all had 4.56's and wished they went with 4.88's, and I plan on 37's when these tires need replaced.

I lucked out on this diff cover, I ended up finding it for sale on GMfullsize. The guy had it on his rear end for 10K and decided to upgrade to the 14sf, I ended up paying $165 shipped from Cali. I believe it goes for $350 or better at 4 Wheel Parts. I would like to get the tranny pan too, but that will have to wait for more funds. Or this dang money fairy!

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Originally Posted by MKader17

What kind of oil/additive is recommended? I like that diff cover, I'm going to have to look into getting one

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Are you going to re-use your G80? Maybe Gasguzzler could chime in on this to clairify the info I was given. But, from what I was told the G80 does not require a LSD additive or friction modifier. Neither did the True Trac I'm running, just straight sythetic gear oil.

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Originally Posted by 567234ta

well ive already got the 4.56's just not installed yet. with a 37" it should make it pretty close to stock rpms.

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let me have them so I can run them with my 33's lol

No additive on the stock axle with GM syth lube.

I'm going detroit true trac for the rear. Good to know I don't need any additive

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Originally Posted by 2001si3rr@

I'm running Mobil 1 75 90 front and rear for break in purposes, after 1500-2000 miles I'll switch to maybe Lucas or something. The front called for 80-90 sythetic and the rear called for a 75-90 sythetic. I'm one of those guys who likes to use what GM recommends, but they want 34-35 dollars a quart for the Delco synthetic 75-90 for the rear, and 8 or so bucks for the 80-90 synthetic for the front. I can deal with the front stuff, but seriously 34-35 bucks a quart before taxes! They can keep that stuff, and when it goes on sale I'll pick some up.... So I'll break them in with the 75-90 Mobil 1 and go from there.

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Where are you looking?!?! I can find it for $18. Hell, Royal Purples stuff is 17 and change. If you look well enough you can get it for $11 in some places.

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Originally Posted by cjriojas

Where are you looking?!?! I can find it for $18. Hell, Royal Purples stuff is 17 and change. If you look well enough you can get it for $11 in some places.

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Yeah, I know you can get it cheaper. I was talking about the Delco Synthetic, the dealer wants $34-$35 a quart plus tax.

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Originally Posted by 2001si3rr@

Yeah, I know you can get it cheaper. I was talking about the Delco Synthetic, the dealer wants $34-$35 a quart plus tax.

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i was talking about delco synthetic also. i can get it for $18 and if i look hard enough probably cheaper and its not from the stealership.

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Originally Posted by cjriojas

i was talking about delco synthetic also. i can get it for $18 and if i look hard enough probably cheaper and its not from the stealership.

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Ok, gotch! Dealership around here are stuck at list price, they won't budge much.

how did you roll around with 3.73s. my truck has only been lifted on 35s for one week and i can't stand them. these 30mph windy days i know kill my tranni. i just leave over drive out sometimes.

I drove my truck for a week with 3.73's on 35's and said no thanks. Parked it and drove the 4 cylinder beater until the 4.56's came in

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Originally Posted by small1town9kid

how did you roll around with 3.73s. my truck has only been lifted on 35s for one week and i can't stand them. these 30mph windy days i know kill my tranni. i just leave over drive out sometimes.

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Honestly, I had it tuned about a week after the lift and 35's cause I couldn't stand it either. A tune will help out alot, but gears would be best. I daily drove it for a year on the tune till I got everything for the gear swap. She was actually pretty peppy with just the tune. Where in Texas are you located?

yeah lol the tune dale did on my truck saturday improved it 10 fold. i can't wait for 4.88s

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Originally Posted by small1town9kid

yeah lol the tune dale did on my truck saturday improved it 10 fold. i can't wait for 4.88s

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I was gonna recommend him, just wasn't sure where you were located! Glad you got it done and happy with it, best change I've ever made was getting the tune. I still need to see Dale about tunning my wifes Tahoe...

Do you plan on bigger tires in the future or you gonna stay with the 35's?

yeah i want 37s. so im thinkin of doin 5.13 gears

I'd stick with the 4.88's or do a 14sf swap when you do the 5.13's. The factory 10 bolt is weak enough by itself, add some 5.13's and 37's to that, and you know what happens. The pinion on my 4.88's was small as hell, and I bet the pinion on the 5.13's is rediculosly small. You'd prolly snap that pinion every time you took it offroad.

Honestly, the 4.88's with 35's is a bit over kill, now that I've spent some time getting used to them. If anyone is sticking with 35's I'd say just go to 4.56's and call her good! I love the torque and response with the 4.88's, trust me she'll s*** and get. If I baby her I can get 14-15 mpg city and about 12-13 mpg highway running 65 mph. Bump that up to 70 mph and turning dang near 2400 rpm's and the gas mileage ain't so pretty!

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Originally Posted by 2001si3rr@

I'd stick with the 4.88's or do a 14sf swap when you do the 5.13's. The factory 10 bolt is weak enough by itself, add some 5.13's and 37's to that, and you know what happens. The pinion on my 4.88's was small as hell, and I bet the pinion on the 5.13's is rediculosly small. You'd prolly snap that pinion every time you took it offroad.

Honestly, the 4.88's with 35's is a bit over kill, now that I've spent some time getting used to them. If anyone is sticking with 35's I'd say just go to 4.56's and call her good! I love the torque and response with the 4.88's, trust me she'll s*** and get. If I baby her I can get 14-15 mpg city and about 12-13 mpg highway running 65 mph. Bump that up to 70 mph and turning dang near 2400 rpm's and the gas mileage ain't so pretty!

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thats one of the main reasons i went with the 4.56's. the pinion on 4.88s or higher gets too small and is not as durable.

i yeah i want a SAS and 40s one day but for now it's gunna be 4.88s or 4.56s.

37's on a 10 bolts yikes! i question the longevity of that combo.....