4l60 vs 6l80

[Ont240]

You're complaining about how the 6L80E's tcm was programmed by GM OE to behave.
It always tries to delay / discourage / avoid downshifts, especially to 1st if at all possible (except for WOT).

3.08 axle gear makes all the above that much worse. Blame GM OE & CAFE MpG test score bullschidt for that too.
Every GM truck with a 4L60E should've come with 3.73 or 4.10. Every GM suv with a 6L80E should've come with 3.42 or 3.73. Transmissions would've lasted longer.

4L60E & 3.42: . . . . . . 10.47 . . . . . 5.57 . . . . . . . 3.42 . . . . . . . . 2.39
6L80E & 3.08: . . 12.41 . . . . 7.28 . . . . 4.72 . . . . 3.55 . . . . 2.62 . . . . 2.06
Clearly your 6L80E's last gear is not enough to cruise @ 70MpH, which calls for a downshift (if not a double-downshift?).
Once you've moved off of the redlight/stopsign, your 6L80E will try to avoid its 1st gear til it stops again; kinda like it wishes it were a 5speed?
4L60E & 3.73: . . . . 11.41 . . . . . . 6.08 . . . . . . . 3.73 . . . . . 2.61
6L80E & 3.42: 13.78 . . . . 8.08 . . . . 5.24 . . . . 3.94 . . . . 2.91 . . . . 2.29

3.42 would help the 6L80E quite a bit - it's the GM OE Tow Pack gear, by the way. Note that tow ratings improve as axle gear improves, for a very good reason.
Does suzi's soccamamabile, REALLY need 4WD?

GM OE cares less about what you think than it cares about what CAFE MpG scores think -
otherwise every GM suv with a 6L80E would have 3.42 or 3.73. (4.10 is for REALLY Heavy Duties, 4.30 is for oversize tires.)
If you want to do something about the awkward shift points, and you are unwilling or unable to to do anything about the axle gears,
the only sensible option left is to get your tcm tuned.
Clearly, the tune should make it more willing to downshift with less provocation, among many other things ...

HP tuner?

 

[07burban88]

so just curious is the 6l80e better than a 4l60?

 

[strutaeng]

so just curious is the 6l80e better than a 4l60?

Yes, I think so.

The problem with OP's truck is he has very low (numerically) gears, so the engine will downshift a lot to try to be on the higher RPM HP powerband.

General Question: Has tire size been mentioned?

My opinion based on limited knowledge about these 2 transmissions: The 6L80 is a far better transmission overall than the 4L60e. The 6 speeds obviously have their own share of issues, but they are not known for blowing up hardparts like the 4L60e. 4L60s have been documented to basically have glass jaws on several geartrain sections.

I have a few 2500/3500 full size trucks (old SBC 5.7 and 6.0 LS) with 4.10s and my 99 Silverado (5.3) with 3.42, all with the 4L80e. 6.0LS/4.10s are pretty fun to drive and best combination. We also have a 3500 Express van with 6.0/6L90/3.42, and it does do some gear hunting, but not horrible. 3.73 with the 6 speeds on the 1500 chassis I think are a sweet spot overall. 4.10 would be better for a heavier vehicle or larger tires.

In general, the more gears, the more gear shifting, so there's also that to consider.

 

[Prospect62]

3.73 is alright but you loose a little top end

You won't lose any top end with 3.73's, especially with a 6-speed transmssion with a lockup converter.

I've swapped three Crown Vics from 3.27 or 3.55 to 4.10 and never lost any top end and that's with a 4-speed auto (well, one had a 5-speed manual). Granted the Ford 4.6 modular has a slightly differnet power band than a 5.3 GM but not by much.

Unless you're winding it out to redline on the regular and keeping it there (think NASCAR), it won't hurt a bit. Anyone who buys into that myth hasn't ever done it.

All you'll notice with a swap from 3.08's or 3.42's to 3.73 or even 4.10 is increased acceleration and a more lively, comfortable driving experience. Yes, your highway cruise RPM's will increase slightly but effect on MPG will be minimal and you won't "lose some top end".

I had an 89 K5 Blazer with a TBI 350 and that truck came with 2.73's! GM didn't do that so we could get "top end". They did it for fuel mileage.

If this were an enthusiast vehicle or a vehicle I planned on keeping for a very long time, a gear swap would definitely be on the list even with the cost of having to do both front and rear. Luckily, I have been finding that a good tune can make even a 3.08 equipped GMT900 feel just fine for daily driving.

 

[mikez71]

6l80 1st ratio 4.03
4l60 1st ratio 3.06
4l80 1st ratio 2.48

6l80 ppv uses 3.08, 4l60 ppv uses 3.73.
12.42 vs 11.41 final 1st gear ratios..

6l80 w/3.42 = 13.78
4l60 w/4.10 = 12.55
4l80 w/4.10 = 10.17

Am I doing this right?
If so, a 6l80 w/3.08 beats or (nearly) matches any 4l with 4.10's.
And a 6l80 w/3.42 is close to a 4l60 w/4.56. (13.95)

I'm not saying what you guys said isn't true.
Just not equal comparisons with different vehicles, motors, transmissions, and usage.

ALSO, if you swapped to shorter gears WITHOUT tuning, you would feel it's stronger just because all your shift points have moved up. (relative to where it should be)
If you swapped to taller gears without tuning, your shift points would all be earlier, combined with the gearing disadvantage, extra bad feeling.
NOT a true comparison of ratio change alone.

For commuting purposes, it maybe diminishing returns.
Gears hunting, purely a tune issue.
(if you simply tune it to NOT shift into 6th at 38mph is a good start!)
Damn CAFE standards! am i right?

YES, I like the 6 speed over 4...
YES, hptuners is useful, but time consuming.

 

[07burban88]

can one swap in a 6l80e into there 07 suburban than came with 4l60e?

 

[Marky Dissod]

so just curious is the 6l80e better than a 4l60?

Of course it is - 6 gears vs 4, wider gear spread with more advantage in the city, greater durability vs the 4L60E ...

can one swap in a 6l80e into there 07 suburban than came with 4l60e?

Very strongly doubt it.
4L60E are usually controlled by a PCM, P is for Powertrain, as in, both engine and transmission at once.
It MAY be possible to control a 4L60E with a TCM? (Meaning there's a separate Engine Control Module that can legibly converse with that TCM? Not sure ...

Know for a fact that a 6L80E absolutely requires a TCM and an ECM that can legibly converse with that TCM.
So, IFF it can be done, it'd use an ECM that can legibly converse with a 4L60E TCM AND a 6L80E TCM (obviously not at the same time).

 

[mikez71]

Powertrain swap solutions is apparently working on a 10l80 swap for gen4 4l60/80s,
but not available yet...

https://powertrainswapsolutions.com/genv-4lxx

 

[Joseph Garcia]

My stock 3.42 gears with the OEM GM tune were OK. As stated above ad nauseum, the transmission was always looking for the highest gear to shift into, and while my 6.2 did not have any issues with living in the lower RPMs, it certainly was not performing to its potential.

The BlackBear tune to my transmission with the 3.42 gears was definitely noticeable, in that the transmission had less tendency to move quickly to the highest gear, and the 6.2 spent more time operating in a bit more friendly rpm power zone, particularly while accelerating. I did not notice a change in mpg, but quite frankly, I don't generally track my mpg or have any concerns about about downward changes in it.

The change from 3.42 gears to 4.10 gears with the original BlackBear tune (3.42 gears) was dramatic. The 6.2 felt more peppy throughout the transmission's gear range with higher rpms in each gear. Acceleration was much improved, with almost like a slingshot effect, as the 6.2 wound out to 6000 rpms. BIG smiles per mile. I lost approximately 1-2 mpg in the city (more heavy pedal usage) and 1 mpg on the highway. Passing at highway speed was actually fun.

The addition of a BlackBear tune to my 4.10 gears delivered another noticeable improvement in the transmission's gear shifting. Shifting was smoother, and for any given speed driving around the city, the transmission was not constantly searching for the highest available gear, but rather seemed to stay in a lower gear that better suited the power and torque bands of the 6.2. BIGGEST smiles per mile.

 

[Marky Dissod]

Let's leave out the 4L80E, whose strong suit is its rugged durability, NOT its gear choices or gear spread; those are disappointing, put nicely.
4L80E is still here after all these years, it costs significantly more fuel to operate, it only needs rebuilding every 5 years or so unless you're abusive. Moving on ...

Most typical GM OE configurations, including but not limited to PPVs of their respective eras
6L80 x 3.08: . . . . . . . . 12.41 . . . . 7.28 . . . . 4.72 . . . . 3.55 . . . . 2.62 . . . . 2.06 (6.04 Spread)
4L60 x 3.73: . . . . . . . . . 11.40 . . . . . 6.06 . . . . . . . . 3.73 . . . . . . . . 2.59 (4.40 Spread)
6L80 wins, duhr ... especially stopsigns and redlights, in towns and cities, on any highway, especially on long steep hills. 4L60E loses on points to 6L80E.
Towns & counties & cities & states cannot print money like sovereign countries do, so I get why GM chose these axle gears, but I *disagree* ...

1500 Tow Pack Gear Option
6L90E x 3.42: . . . . 13.78 . . . . 8.07 . . . . 5.23 . . . . 3.93 . . . . 2.91 . . . . 2.29 (6.04 Spread)
4L60E x 4.10: . . . . . . . 12.54 . . . . . 6.68 . . . . . . 4.10 . . . . . . 2.85 (4.40 Spread)
6L80E wins again, duhr.

What should've been GM's 1500 (1675?) tow pack option (think it was a 2500 'base' option?)
6L80 x 3.73: . . . 15.03 . . . . . 8.80 . . . . 5.71 . . . 4.29 . . . . . 3.171 . .2.50 (6.04 Spread)
4L60 x 4.30: . . . . . . 13.16 . . . . . . 7.01 . . . . . . 4.30 . . . . . . 3.01 (4.40 Spread)
In both cases towing MpG might go down a bit (less than you think), but both transmissions would last longer with these gears.
Looking for better MpGs? Tune these gears to shift very conservatively in Normal Mode.
In Tow/Haul mode these'd inspire confidence with very little shift confusion.

 

[Doubeleive]

You won't lose any top end with 3.73's, especially with a 6-speed transmssion with a lockup converter.

I've swapped three Crown Vics from 3.27 or 3.55 to 4.10 and never lost any top end and that's with a 4-speed auto (well, one had a 5-speed manual). Granted the Ford 4.6 modular has a slightly differnet power band than a 5.3 GM but not by much.

Unless you're winding it out to redline on the regular and keeping it there (think NASCAR), it won't hurt a bit. Anyone who buys into that myth hasn't ever done it.

All you'll notice with a swap from 3.08's or 3.42's to 3.73 or even 4.10 is increased acceleration and a more lively, comfortable driving experience. Yes, your highway cruise RPM's will increase slightly but effect on MPG will be minimal and you won't "lose some top end".

I had an 89 K5 Blazer with a TBI 350 and that truck came with 2.73's! GM didn't do that so we could get "top end". They did it for fuel mileage.

If this were an enthusiast vehicle or a vehicle I planned on keeping for a very long time, a gear swap would definitely be on the list even with the cost of having to do both front and rear. Luckily, I have been finding that a good tune can make even a 3.08 equipped GMT900 feel just fine for daily driving.

you can do all the math you want but the bottom line is when you create more low end you loose top end.
and you can feel the difference, at least I can. But I am not your average driver
the basic reasoning for most street vehicles to have a higher gear ratio is towing capacity. (gm's reasoning to lower it is epa mandated mpg)
Or if you want to be able to lay rubber down the block just for fun, be first off the line, etc
so YES you do loose some top end, but for most people that are just towing and driving normal it doesn't matter.
in the context of 6000lb suv's if you want to be able to tow a little more and/or have a little less gear hunting on the highway then increase the gear ratio and go about your day.
@Bronson357 a Transmission (TCM) tune would help make the 6l80 on a 5.3 with 3.08 a bit better or more reasonable to drive, a good tune makes a difference. It's probably still going to hunt at highway speed though. Cheaper fix than a gear ratio change

 

[mikez71]

It's great to hear the variety of real world experience!
What I found most surprising, is Mr. Garcia's supercharged 6.2 with short gears..
I would think tire spin should have capped his acceleration already!

Regarding the OPs original issue,
A tune can 100% fix hunting, BUT the COST is higher sustained RPMs...
(and whatever a tune costs)

 

[buckwild27]

I can tell you as a guy that's had all of these combos except for the 3.08 gears because I've known from the jump those are useless. The 4l80 behind even 800hp is still a slow shifting pig. But it is a strong transmission. The 4l60 even built to the max 750hp handling capabilities is still a pile of dog crap. But it is an improvement over the 700r4 that it was before. The 6l80 has by far been the best transmission hands down and I've abused them. My 2013 hade a 5.3l and 6l80 originally came with 3.42 I swapped it and the 2010 to 3.73. I tuned engine and transmission in the 2013 the tow/haul button was tuned out basically and I towed all the time in 6th gear never had a lick of problems with it. It was still going strong when I sold it with 260,000 miles on it. Best mileage i got with it on average was about 16mpg. With the normal way I drive average 12.5mpg. The 2010 with a 6.2l and 3.73 gears with 430hp and the 4l60 pulled roughly 5000lbs with no slouching. But it didn't take long for the 4l60 to meet the inevitable fate. Then I swapped in a lsx376 and a 4l80 and to be truthful the 4l80 and its 40% loss of power is felt right up until the prochager gets spooled up and then it hits 4th gear and turns into a rocket. My 2018 with a 5.3l and 3.42 gears and no tuning constantly shifting gears when towing with tow/haul and in 5th gear. My 2014 with the 5.3l and 3.42 gears the AFM is turned off the transmission is tuned and it pulls great without a bunch of useless shifting. Without a trailer on it will throw you back in the seat a little bit. And it has over 307,000 miles on it. Ultimately if you pull a trailer 3.73 or 4.10's are a must. For everything else you could get away with 3.42's hands down without question the transmission tune needs to happen no matter what. I bought a Dirty max to tow with now so I'm sticking with the 3.42's in the daily driver.

 

[Tazio]

Have you tried driving it in towing mode? This will keep the trans out of the two overdrive gears until higher speeds.

 

[Prospect62]

Have you tried driving it in towing mode? This will keep the trans out of the two overdrive gears until higher speeds.

That's what I did almost every day before I got my tune. It's just not a long term solution. The aggressive downshifting is just too much after a while.

 

[West 1]

In these trucks with a 6L80 there is no chance of losing top end speed by swapping from 3.08 to even 4.10. The 6 gear overdrive gives the truck longer legs even with 4.10 gears.

With Stock engines in a GM truck I would bet large money that a 4.10 equipped truck will out run a 3.08 equipped similar truck from the start to top speed.

Someone will give the actual numbers but even with 4.10 gears with a 6L80 trans the Top speed at Redline will be close to 150 mph.
These trucks, maybe other than Joe's supercharged 6.2L don't have the horsepower to push a Tahoe/Yukon body through the air to 150. The engine will be stopped accelerating due to wind resistance before it reaches Red Line. I bet with 3.08 gears the truck would hit top speed in 4th gear or maybe 5th gear but not in 6th because it would not have the horsepower to overcome the wind resistance in the 6th gear overdrive. These trucks even with a tune are not going to go 180 mph because they have 3.08 gears. Even the stock base Corvette runs into wind resistance before 180 mph and that car is slippery and has more HP than the truck engines, unlike these huge boxes we drive.

The taller gear is not a worry for top speed. It will affect MPG at speeds over 75 as your RPM starts getting higher.

 

[Marky Dissod]

GM's 6L80-PPV, vs, well, Marky Dissod's idea of a 6L80-PPV ...
6L80 x 3.08: . . . . . . . 12.41 . . . . 7.28 . . . . . . . . 4.72 . . . . 3.55 . . . . . 2.62 . . . . 2.06
6L80 x 4.10: .. . . . 16.52 . . . . 9.69 . . . . 6.28 . . . 4.72 . . . . 3.49 . . . . 2.75
In other words, if both vehicles share the same size tires, the 4.10 vehicle has the decided acceleration advantage.
Plugged some numbers into https://www.blocklayer.com/rpm-gear
5600RpM, 6L80, 265/60R17 (29.51" tall), 3.08 vs 4.10

GM's 3.08-PPV will need a 3-4 UpShift @ about 104MpH
MD's 4.10-PPV will need a 4-5 UpShift @ about 104MpH
Both have enough power to hit 104MpH, but the 4.10-PPV WILL hit it sooner.

GM's 3.08-PPV will need a 4-5 UpShift @ about 139MpH
MD's 4.10-PPV will need a 5-6 UpShift @ about 141MpH
If the 3.08-PPV has enough power left to hit 139MpH, again, the 4.10-PPV will hit it sooner.

Joseph Garcia did it right . If you don't care about acceleration,
you'll still spend lots more time in 6th, and less time downshifting less often for lack of power to the ground.

 

[mikez71]

One thing you guys are not accounting for, is that lower gears (more gear reduction) is not as efficient.
There must be a reason @Doubeleive says he lost some top end, I don't doubt him.
I'm not saying that's THE reason, peak engine torque/horsepower rpms may play a factor as well.

There's always tradeoffs..

I will say, for cruising around, when I had a more aggressive tune (that I was initally super happy about)...
.. the constant rpms winding up got tiring, for the speed I was going..

Granted a lower gear would allow you to have more torque at low rpms, so should be better in that regard..
But you'll be shifting sooner, and possibly have an extra shift..
For example I used to cruise in 4th 80% of the time, but now I'm between 4th AND 5th 80% of the time.
I could raise 5th (and might) but then my cruising rpms aren't as comfy..
And with the factory tune, power delivery and throttle position aren't linear, and at light throttle and high rpms, you tend to slow back down..
So now there's more accelerator modulation going on...

Tune it you say! Well maybe, but sometimes the more I change things, the more things need re-tuning!
And actually changing accel pedal position vs throttle position can put you in REP mode pretty easily..
There is a work around I've heard, but it's more involving than just changing one map.

 

[Marky Dissod]

One thing you guys are not accounting for, is that lower gears (more gear reduction) is not as efficient.
There must be a reason @Doubeleive says he lost some top end, I don't doubt him.
I'm not saying that's THE reason, peak engine torque/horsepower rpms may play a factor as well.

There's always tradeoffs.

The efficiency drop from 3.08 to 4.10 at the axle (PPVs did not power 2 axles then) is made up for by keeping the engine between peak torque & power longer,
as well as spooling up the torque converter sooner and more quickly. One can safely guess which gear CAFE MpG testing implicated.

The tradeoff that someone else has already mentioned in a different thread is driveshaft harmonic vibrations.
The 4.10-PPV would need a lighter specially balanced driveshaft to safely exceed 104MpH, let alone 139MpH, which is another way of saying GM cheaped out.
In other words, 3.08-PPVs use the standard GM-OE driveshaft every other GMT900 swb suv uses ... ceding the market to Ford's PIS & PIU by default in many cases.

 

[Marky Dissod]

Granted a lower gear would allow you to have more torque at low RpM, so should be better in that regard.
But you'll be shifting sooner, and possibly have an extra shift.
For example I used to cruise in 4th 80% of the time, but now I'm between 4th AND 5th 80% of the time.
I could raise 5th (and might) but then my cruising RpM aren't as comfy.
And with the factory tune, power delivery and throttle position aren't linear, and at light throttle and high RpM, you tend to slow back down.
So now there's more accelerator modulation going on.

Tune it you say! Well maybe, but sometimes the more I change things, the more things need re-tuning!
And actually changing accel pedal position vs throttle position can put you in REP mode pretty easily..
There is a work around I've heard, but it's more involving than just changing one map.

If you cross-pollinate various GM OE tune variables/numbers with each other to create your own GM-OE inspired tune,
eventually you will still find that you need those workarounds that more experienced tuners are using to improve things like throttle response and avoiding REP mode.