4.10 vs 4.88 (towing)

Best gear for towing?

  • 4.10

    Votes: 2 66.7%
  • 4.88

    Votes: 1 33.3%
  • Something else

    Votes: 0 0.0%

  • Total voters
    3
  • Poll closed .
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Reprise

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I'll spare the details here, but I may need a new ring / pinion for the Sierra.
Looking at Rock's site, they don't sell a direct replacement (4.10) - but they do offer two R&P in 4.88

I know it'll use more gas. That's a given. But the truck had 4.10, anyway. For the record, it's a RWD 6.0L Crew, w/ 4L80.

From a towing perspective...b/c that will be the main use of the truck... would you go with the stock 4.10 or jump on the 4.88 for replacements? I'll put a poll up for a few days. If you vote, I'd like you to post the 'why' behind your answer.
And you can post w/o voting, but what's the fun in that?

Realizing you'll be asking for 'scenarios', here they are...
a) Mountainous vs. Flat
b) 5000 / 7000 / 10000 lb
c) Otherwise stock vs. Intake / mild towing cam
d) 'Technical' stuff not covered above

Thanks!
 
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Mooseman

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Dec 4, 2011
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Please refresh our memories on which engine this Sierra has.
 

Reprise

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Of all people, I didn't expect you to ask, since you recommended I replace the 5.3 with it... :smile:

6.0L LQ4
 

northcreek

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Jan 15, 2012
3,310
WNY
I can/have lived with 4:10, but I have had 4.56 gears and you pretty much resign yourself to secondary roads with those. Your overdrive trans will help you a bit with the 4.88 gears but, it really depends on what roads you will spend most of your driving on.
On the bright side 4.88s will really give that Sierra a kick in the pants and tow like a bear.
 

Mooseman

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Dec 4, 2011
25,257
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Of all people, I didn't expect you to ask, since you recommended I replace the 5.3 with it... 😄

6.0L LQ4

You have how many trucks? We can't keep up with your whole fleet. :biggrin:

I'd have to agree with @northcreek . Unless you're towing a mobile home, it'll be screaming down the highway. So maybe you might have to drop down a gear on some steep hills but to me, that's normal.

Right now, I'm towing my aluminum covered sled trailer (~3000 loaded with two Yamaton sleds) with my 4.2 TB and 3.42's. I can maintain 100km/h in 3rd and very occasionally I have to drop it to 2nd on steep hills. It doesn't bother me and I'm towing so I know my MPG are gonna suck. With just one sled loaded, I can even use OD on flats. The TC still locks up in 3rd holding a steady speed.

Have you actually tried to tow with your current gears? It might not be as bad as you think.
 

Bow_Tied

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Dec 21, 2014
453
London, ON
20% is a big jump. I'd avoid it for a regular driver. 4.33s, ya 4.56+, no. jmo
 

Reprise

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Availability is the reason I was asking; not so much b/c I had an 'itch' to scratch...lol.

Plan is that this truck is a dedicated tow vehicle, and the Voy (3.73) is my DD / runaround town rig. The Sierra would be towing on the interstate almost exclusively, except when dropping off the trailer to sightsee at a destination, or if the Voy broke down.

The Voy is a much more comfy DD, so it would get most of the non-tow service. Nice thing is that it could be a bkup TV, in an emergency.

I know (?) the engine is going to be turning a higher RPM at the same speed, if I go with the bigger gear. I just always read about ppl putting in big gears for tow.

If Rock had 4.10 for this axle, I'd order that. Looks like I might have to source these elsewhere -?
 
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northcreek

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Jan 15, 2012
3,310
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Just for a rough comparison, the 4.88s will be somewhat like driving your truck with 4.10s and shifted out of overdrive. If you can live with that...go for the stump puller gears.
 

Kelly@PCMofNC

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Mar 16, 2013
183
Honestly I'd prefer the 4.10. I realize it's a big cost, butttt......4.10 + roots supercharger (i.e. Maggie) = killer towing without taching out on the highway. :smile:

Gears/RPM etc are kind of a personal taste but even if I were staying n/a I would stick with the 4.10, 4.88 would be too much for me unless I was never getting above 45-50mph.
 

Reprise

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Appreciate everyone's replies. I think the consensus is leaning toward sticking with the 4.10 that came with the truck. And I'm just fine with that.

The problem now is finding that gearset. GM part # is 26091710, which has been discontinued everywhere. Even Spicer's e-commerce site doesn't list an equivalent (they do offer the 4.88, which helps explain why Rock (& a couple of other sites, like Summit) offer that).

That being said, I'll bet I can eventually find a replacement, eliminating 'GM' from the interchange criteria. I know that 4.10 for a Ford with 9.75 Dana axle is readily available, and I have other options, such as finding an entire replacement axle (I've sourced one from a place in MO, and it may be the way to go, after all is said and done - it'll run about $800, if I pick it up - I've already been in touch with the guy) Only issue there is that it has 6-lug hubs, but the axle should be otherwise identical (wheel-to-wheel width, etc.) And it's a 4.10, too. Only risk there is if that axle has an issue, since it's in a junkyard.

Honestly I'd prefer the 4.10. I realize it's a big cost, butttt......4.10 + roots supercharger (i.e. Maggie) = killer towing without taching out on the highway. 😄

Man, I love blowers. But my research tells me that a turbo may be the way to go for towing in mountainous terrain / elevations, vs. a blower. Feel free to refute me; you do this for a living. And there's all kinds of room in the engine bay for the gear, of course.
I know I'm going to put a towing cam in the truck (if I ever get the rear fixed!) and put in . Then I'll reevaluate after I get a couple of trips in with that setup.

At this point, I doubt I'll go down the FI path, but you never know. I know for sure that I'm not going with diesel; I'll never recoup the added cost, and the maintenance is $$$$ and foreign to me, besides.
 

Wooluf1952

Member
Nov 20, 2011
2,663
Milwaukee, Wisconsin
:twocents: If you can't find the 4:10 gears you could ramp up the tire size.
 
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Reprise

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Try this guy for a gear set. He has a differential graveyard. He travelled across the state to buy a posi unit that I had.
http://www.rearsgears.com/

Appreciate the link. While I was able to manipulate his search engine to select the QS axle, his offerings are 4.56 / 4.88, and three in the 5.xx sizings. Via Yukon Gear.

I had been on the Yukon site earlier, and because my Dana 60 is a 'standard' 35 spline, 12 ring gear bolt, etc., etc... I can get a 4.11 or a 4.30 set from them. The QS resource I've been using says that although the Trac-Loc case is a little thicker than 'Dana stock', I can fit a gearset up to 4.30 in the carrier (although I'm guessing I might have to reshim it).

So...given that, I should have a source for a gearset, via approaching this from the 'Dana 60' end, vs. the Quadrasteer / GM end. 4.11 would be mucho compatible with my speedo, etc.; 4.30 would give me a little 'oomph' for towing (but not be super crazy). I'm leaning toward the 4.30, at this point. But I think I might need to find a local resource who could set up / install the gearset properly, since either would be a new gearset.

I'll pull the cover tonight / tomorrow, and we'll see what the existing gears look like, and will figure out next steps from there. Meanwhile, this thread has served its purpose, which is determining that 4.88 gearing is likely suboptimal (unless I were using big-ass tires / wheels, which I'm not.)

And... I have an alternative to the 4.10, if it winds up being trashed. Two, actually, if I source the replacement axle from that junkyard (how the case internals look like will determine that. I'll go back to my other thread to document the 'what' and 'why' I might need a replacement housing / axle.)

:twocents: If you can't find the 4:10 gears you could ramp up the tire size.

I could; during my research, I found out that's part of the reason why the big 6.xx / 7.xx gearsets are offered - to put the final drive back into something manageable, for those running really big tires.

Thing is, for my purposes, I plan on using a highway tire, and I've already sourced a nice set of 17" wheels, cheap. So I'm going with a 265/70/17 LT tire (10 ply 'E'). Appreciate the idea, though - it was a good one. And if you missed it from earlier threads on this truck, it came to me with a set of BFG A/T KO2 315s on H2 rims (34" high). I sold 'em last weekend; they'll fund my new wheels / tires.

Thanks again to all who replied.
 

northcreek

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Jan 15, 2012
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WNY
Appreciate the link. While I was able to manipulate his search engine to select the QS axle, his offerings are 4.56 / 4.88, and three in the 5.xx sizings.
You might try contacting Gevo, he has alot of stuff that isn't accessed via search.
 

Reprise

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Took your advice & e-mailed him, explaining the situation. I'll post back if he has the match (although like I told him... if the Yukon 4.11 / 4.30 sets will work just fine, I'm OK with going with one of those).

I figure a 'gen-u-wine' copy of GM # 26091710 would cost me dearly at this point; the Yukon sets are about $300.00 And if the pumpkin itself is ruined, I've got access to an entire replacement axle for about $800 (plus gas both ways...lol) We shall see...
 

northcreek

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Why is this particular axle such a bastard ? They must have made a million of them....seems odd.
 

Reprise

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If you're talking about the Dana 60 internals...I don't know about 'a million', but 10s / 100s of thousands wouldn't be an exaggeration. Although Dana has a lot of revisions / part #s, and the axle went into a LOT of applications - mostly as a front axle, though. Also, the part #s for this particular axle are 'oddball' ones over at Dana / Spicer (that's another story, entirely).

If you're talking about the actual axle housing... nope. They're rare as hen's teeth, because very few people bought Quadrasteer-equipped vehicles, back in the day. By the time the GMT-900s came out, the option (RPO: NYS) was discontinued.
Three reasons for that: High initial cost (> $4000 in early 2000's dollars, although GM lowered it toward the end of the run); poor promotion by GM, and dealers not showcasing them often (both limited stock and the high cost).

As to why I don't just rip out the system (yet) - it cuts about 10ft off the turning radius, and for something with a 153" WB, that's significant. There's also some towing benefits, as well.
Also... see above about 'rare'. That type of thing appeals to me. And the steering mechanicals & electronics work beautifully. While they do, and for as long as I can get parts, I want to keep the system. Especially since the rest of the truck is a 'keeper', too. :wooot:
 

northcreek

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Jan 15, 2012
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Thanks for 'edumacating' me, I did not know anything about the Quadrasteer...good stuff.
Knowing the rarity and turn radius, I could live with the 4.30 ratio.
 
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Reprise

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If you're interested in the system, take a look at the GM video on this page (it's near the top):
 
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littleblazer

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Jul 6, 2014
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I'd personally go 4.10s. We lose 4th in the red truck pretty regularly and even with 4.10s you're spinning 3300 in 3rd to do 65-70mph. The 4.30s would probably be okay...
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
Wish I had the 5.3 right now. Towing in a head wind is brutal.
 

BrianF

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Jul 24, 2013
1,192
West central Sask.
Another for the 4.10 option. Really is your best compromise between highway gears and the 4.88/56 gears. Unless your truck is 100% hooked up to a heavy, like max weight load, you will be absolutely screaming down the highway.

I drove some old, low geared grain trucks, military trucks and they are an absolute bear to keep at or even near highway speed. Off road or under max load and they were great.

I don't tow much if at all anymore with my 3.42 geared Tb but my 2017 3500 SRW is equipped with 3.42 gears. Now it is great unloaded ripping down the highway but because of the power and trans gearing, it still works great under load. I just lock out one or both overdrive gears and it keeps it in the power band. But this is only due to the massive power it has on demand.
 
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Reprise

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I just lock out one or both overdrive gears and it keeps it in the power band. But this is only due to the massive power it has on demand.

DMax / Allison ? Just curious...


Back to the teardown...I got the diff cover off a couple of hours ago...pretty heavy / bulky with the rack / pinion & tie rods attached (someone replaced with Moog...thank you!).

Thankfully, I didn't drop / damage it (except for a 1/4 braided copper ground strap on the harness that just disintegrated when I moved it.) Haven't spun the ring fully around yet, but from what I see so far, the ring gear doesn't look marred / broken teeth / worn. Fingers crossed. And that should be 'good' for the pinion gear, too (at least the toothed section of it).

I did pull out a couple of larger metal shards from between the bearing caps; they're thinner, shiny, and sharp-edged, matching what came out of the drain plug earlier (but these are bigger). So that says 'bearing', to me. Expecting to see at least one very chewed-up bearing, when I get the rest of this thing disassembled. Hopefully, the case is intact, along with the pinion gear shaft. Fun, fun, fun! LOL
 

Reprise

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Mods...let's close this thread, as I've got this question resolved to my satisfaction, and I can source either a 4.10 / 4.11 / 4.30 without issue, should I need to (latest info looks to be 'not', after seeing / inspecting them.)

Moving the diff conversation back to my original thread. Thanks.
 

Mooseman

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Dec 4, 2011
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