5.3 to 6.0 swap complete... But

[Mudsport96]

Yeah the 4l60e is basically an electronic version of the 700r4. And the steep first gear was to get the underpowered engines of the 80s enough gear reduction to move the vehicles from a stop. Some of those cars were almost as heavy as a Suburban of the Era, and had a 145hp trying to turn a 2.73 or God forbid a 2.56 gear. So the 3.06 first gear would give enough multiplication to start moving, and then lug through 2nd to a decent speed.

 

[S33k3r]

Yeah, the numerically lower gear ratio is kinda of a common misconception the requires a rear axle regear on the 4L80e. Not really on a lighter weight 1500 vehicle. My Silverado has 3.42 gears. 3.73 I think would be ideal. 4.10 probably overkill for daily driving.

Most vehicles that offered that transmission had 3.73 or 4.10s, but that's because they are overall heavier and higher GVWR.

Actually, the opposite is true about the 4L60e-family: the first gear is TOO low (numerically higher), and the 1-2 ratio DIFFERENCE is too much. Do a comparison with the other 4 speeds from the other manufacturer of that era and you will see the odd duck. We've discussed this on a different thread before.

Overall, the 4L80e ratios are much closer to each other, and 4th is actually higher than the 4L60e, so cruising RPM is a bit higher, but only slightly. It's good for highway towing because it puts you higher in the powerband of the LS engines. Once you drive one side by side, you will know what I'm talking about.

I have a 2003 Sierra Denali with a 4l65e and 4.10s. It is by far the highest accelerating, best driving truck we have. I have a 2004 Silverado 2500 that was never reprogrammed for oversized tires, so it is a dog off the line ($l80e/3.73s). I have a 2005 Suburban 2500 with the 4l80e and 3.73 gears. All 3 are 6.0s.

I list the above out to let you know I have some experience with these combinations. Because my experience has been that the 4l80e has a mechanically higher gear than the 4l60/65, such that the shift to 2nd takes longer in a 4l80. Keep in mind I realize the Sierra Denali is a lighter vehicle and have taken that into account.

From this article: 4L80e Transmission—All You Need to Know
"The 4L80e uses four forward gears and one reverse gear in the following ratios! First gear:2.48, second gear:1.48, third gear:1:0, fourth gear:0:75, and reverse gear:2.07. It has a maximum input torque of 440 lb-ft and a maximum output torque of 885 lbs-ft with a vehicle weight rating of 800 lbs."

From this article: 4L60E Identification: Complete Guide


From this article:
4L65E TRANSMISSION SPECS AND UPDATES
"The 4L65E transmission has a weight of 194.6 pounds. It’s gear ratios for the first gear, second gear, third gear, and fourth gear are 3.059-to-1, 1.625-to-1, 1-to-1, and 0.0696-to-1, respectively. What’s more, the 4L65E features five-pinion planetary carriers."

According to those articles, the 4l60 should be faster off the line, faster in 2nd gear, the same in 3rd gear, and a little slower in 4th. The 4l60 also has the advantage in verse, with a 2.29 gear vs. the 4l80 2.07.

This does fly out the window if you regear, and will be modified by the final drive ratio.

If you have a better source of information, please share it. I don't mind being wrong, but I want to have the information to back up what I say. I'm a member of about 12 truck/SUV forums. Many of which are not as nice as the folks here.

[EDIT] Something I don't recall seeing in this thread that makes all the difference in the world are the programmed shift points. Having a perfectly geared set up and crappy shift points can really ruin your day.

 

[strutaeng]

I have a 2003 Sierra Denali with a 4l65e and 4.10s. It is by far the highest accelerating, best driving truck we have. I have a 2004 Silverado 2500 that was never reprogrammed for oversized tires, so it is a dog off the line ($l80e/3.73s). I have a 2005 Suburban 2500 with the 4l80e and 3.73 gears. All 3 are 6.0s.

I list the above out to let you know I have some experience with these combinations. Because my experience has been that the 4l80e has a mechanically higher gear than the 4l60/65, such that the shift to 2nd takes longer in a 4l80. Keep in mind I realize the Sierra Denali is a lighter vehicle and have taken that into account.

From this article: 4L80e Transmission—All You Need to Know
"The 4L80e uses four forward gears and one reverse gear in the following ratios! First gear:2.48, second gear:1.48, third gear:1:0, fourth gear:0:75, and reverse gear:2.07. It has a maximum input torque of 440 lb-ft and a maximum output torque of 885 lbs-ft with a vehicle weight rating of 800 lbs."

From this article: 4L60E Identification: Complete Guide
View attachment 424364

From this article:
4L65E TRANSMISSION SPECS AND UPDATES
"The 4L65E transmission has a weight of 194.6 pounds. It’s gear ratios for the first gear, second gear, third gear, and fourth gear are 3.059-to-1, 1.625-to-1, 1-to-1, and 0.0696-to-1, respectively. What’s more, the 4L65E features five-pinion planetary carriers."

According to those articles, the 4l60 should be faster off the line, faster in 2nd gear, the same in 3rd gear, and a little slower in 4th. The 4l60 also has the advantage in verse, with a 2.29 gear vs. the 4l80 2.07.

This does fly out the window if you regear, and will be modified by the final drive ratio.

If you have a better source of information, please share it. I don't mind being wrong, but I want to have the information to back up what I say. I'm a member of about 12 truck/SUV forums. Many of which are not as nice as the folks here.

[EDIT] Something I don't recall seeing in this thread that makes all the difference in the world are the programmed shift points. Having a perfectly geared set up and crappy shift points can really ruin your day.

Fair enough and good observations.

Yeah, you can't directly compare a 1500 with a 2500 accelerating. The 2500 is a heavier vehicle: heavier frame, heavier transmission, heavier axles, heavier brakes...you get the picture. They were meant for towing, not for speed

My 99 Silverado is also faster with a 5.3/3.42 gears vs my suburban 2500 LQ4/4.10. Not a fair comparison because the suburban is maybe 1200-1500 lbs (?) heavier. Same transmission and tires.

The 4L80E will stay in a better RPM when shifting gears is what I'm trying to say. No huge drop in RPM.

The fact that the drag racing guys cranking huge numbers in the HP/TQ favor the strength of the TH400/4L80e is what we were hinting at the OP since he mentioned he was going to beef up his engine. 2wd swap is pretty straightforward. Maybe an overkill. IDK. I've never heard anyone going back to a 4L60e after swapping and running a 4L80e: on the strength and durability department, there's no comparison.

Edit: one of my favorites likes of the 4L80e is how smooth it operates compared to the lighter duty transmission...

 

[S33k3r]

Edit: one of my favorites likes of the 4L80e is how smooth it operates compared to the lighter duty transmission...

You ain't felt nothin' 'til you drive with an Allison. My Duramax has the 6 Speed. It shifts like butter. It is AMAZING!

 

[Mudsport96]

I have a 2003 Sierra Denali with a 4l65e and 4.10s. It is by far the highest accelerating, best driving truck we have. I have a 2004 Silverado 2500 that was never reprogrammed for oversized tires, so it is a dog off the line ($l80e/3.73s). I have a 2005 Suburban 2500 with the 4l80e and 3.73 gears. All 3 are 6.0s.

I list the above out to let you know I have some experience with these combinations. Because my experience has been that the 4l80e has a mechanically higher gear than the 4l60/65, such that the shift to 2nd takes longer in a 4l80. Keep in mind I realize the Sierra Denali is a lighter vehicle and have taken that into account.

From this article: 4L80e Transmission—All You Need to Know
"The 4L80e uses four forward gears and one reverse gear in the following ratios! First gear:2.48, second gear:1.48, third gear:1:0, fourth gear:0:75, and reverse gear:2.07. It has a maximum input torque of 440 lb-ft and a maximum output torque of 885 lbs-ft with a vehicle weight rating of 800 lbs."

From this article: 4L60E Identification: Complete Guide
View attachment 424364

From this article:
4L65E TRANSMISSION SPECS AND UPDATES
"The 4L65E transmission has a weight of 194.6 pounds. It’s gear ratios for the first gear, second gear, third gear, and fourth gear are 3.059-to-1, 1.625-to-1, 1-to-1, and 0.0696-to-1, respectively. What’s more, the 4L65E features five-pinion planetary carriers."

According to those articles, the 4l60 should be faster off the line, faster in 2nd gear, the same in 3rd gear, and a little slower in 4th. The 4l60 also has the advantage in verse, with a 2.29 gear vs. the 4l80 2.07.

This does fly out the window if you regear, and will be modified by the final drive ratio.

If you have a better source of information, please share it. I don't mind being wrong, but I want to have the information to back up what I say. I'm a member of about 12 truck/SUV forums. Many of which are not as nice as the folks here.

[EDIT] Something I don't recall seeing in this thread that makes all the difference in the world are the programmed shift points. Having a perfectly geared set up and crappy shift points can really ruin your day.

Stock for stock those should all true points on paper. But, it is the unseen things that also add to the whole. Torque multiplication in the converters, stall speeds of the converters, gear change speed, rpm drop between gears keeping engines in their sweet spot.
For instance the 60e 1-2 drop 6000rpm to 3100. The 80e is 6000 to 3600, so for the same engine, if you have say 250 lbft of torque at 3000 and 350lbft at 4000... which transmission gets to max torque first? The one that drops rpm to almost 3000 or the one that drops rpm to 3600 ( 600 rpm closer to max torque)?
Also converter torque multiplication is typically higher in the 80e so the converter multiplies your torque by say 1.75 so 100lbft at the crank side of the converter is 175lbft at the turbine turning the input shaft. A 60e is closer to 1.5 I believe simply because it is a far weaker transmission overall. That is why torque management nanny was devised when obd2 came out.
But in the end a 60e is okay for stock and mild stuff. But for what he is doing I would get an 80e. A 2800 stall converter and shift kit, and it will accelerate the same if not better than a 60e. Lawrence Tollman on YouTube did that swap in his shortbed Silverado and actually picked up speed short track and dropped a couple tenths to 60mph.

 

[Mudsport96]

Also black magic wizardry.

 

[S33k3r]

Lawrence Tollman on YouTube did that swap in his shortbed Silverado and actually picked up speed short track and dropped a couple tenths to 60mph.

I post the YouTube link often. Was not aware he picked up speed. I just know he had too much final drive ratio with 4.56s, and switched back to his 3.42 (if memory serves correctly). He really needs a 6 speed or 8 speed to take full advantage of his beast. He runs out of gears too fast.

 

[Mudsport96]

I post the YouTube link often. Was not aware he picked up speed. I just know he had too much final drive ratio with 4.56s, and switched back to his 3.42 (if memory serves correctly). He really needs a 6 speed or 8 speed to take full advantage of his beast. He runs out of gears too fast.

You are talking about the black truck and roll racing he lost too much and all the torque from the turbo 8.1 was better suited to the 3.42 gears. The orange short bed is the one I'm referring to.

 

[S33k3r]

You are talking about the black truck and roll racing he lost too much and all the torque from the turbo 8.1 was better suited to the 3.42 gears. The orange short bed is the one I'm referring to.

I haven't followed the orange, short bed. Just the black one.