correct transmission for 6.0

[informi]

I have a 6.0 out of a 02 Yukon Denali. It is going in my 62 c10. I had originally planned to use a Turbo 350 I have, but am now thinking I would like an electronic 4 speed. So I figured the simplest route is to use the same transmission that came with the Yukon originally.

So here are my questions:

1) What model did it come with originally? I was thinking it was a 4l60e, but then I see mention of a 4l70e (or other variants) etc, so not sure exactly which one I need to get to minimize hassle. I would ideally like to use the existing harness/connections as is (if possible).

2)If the transmission I end up with is not the same as the one that came with my 6.0, can my PCM be flashed to work with a different model (ie a 4l80 for instance)?

Been a long time lurker and been able to get all kinds of great info and help. Thanks for any help/input you have.

[BR3W CITY]

They came with an 80e or a 60e for the most part. The 80e is the stock tranny for all the HD trucks, and the 6.0/80 was the only combo available when the 6.0 came out.

You can segment swap the ecm to run another tranny, again for the most part. The 80e also has a second VSS so the wiring needs to be modified.

[informi]

Great that helps. So you mentioned two VSS. I just took a quick picture of what I believe is the transmission part of my harness (its crammed in the corner still connected to the engine so not the best picture) . Do these look like what would go with an 4l80e (because there are two additional connections)?


Can you explain a bit what you mean by "segment swap"?

Thanks again for the help.

[95 S_Trucker]

The yukon denali had a 4L60e transmission.

[BigRed76]

From what I can tell in your picture the big connector is for the 4L60E transmission, the 2-wire connector is for the Vehicle Speed Sensor (Only 1 on a 4L60E), and the 4-wire connector I believe is for the left front oxygen sensor (the oxygen sensor connectors will usually have those little blue safety clips from factory)...

[68GMCCustom]

Actually didn't the 6.0 motors come with a 4L60E-HD up until they came with a 4L65E and even later some with the 4L70E. I guess my point is didn't they come with the heavier duty version of the 4L60E due to the motors higher torque ratings. Not a trans guy but IIRC one difference is 5 vs 4 planetaries or bearings around the sun gear....or some spacial sounding bits.

That said................I'm running a 4L85E behind my 6.0L.

[BR3W CITY]

It was the 80e in the heavy duty stuff, the "ls" 4l60e in everything else. From what I gather, what I call the "ls" 4l60e, is the same as you refer to; the upgraded planetary version of the regular 4l60e, with the bellhousing drilled to the ls pattern (top bolt vs no top bolt). and the 300mm input shaft.

The 65e is again basically the same tranny, with even more modernized internals, a deeper pan, and a different style of tail housing. (iirc its based on a Holden design)

[informi]

Did some looking to see what 4l60es might be available, I have seen them as coming from 1/2 ton/1500s, suburbans, and even a couple that said they came out of an S10. Would a v6 s10 really have the same transmission as a 6.0?

Is there a difference in a 4l60e that came out of a car (like a Camaro) versus one that came in a truck? And do I need to be concerned about what year the transmission is (as compared to my 2002 motor)?

Thanks again for the help.

[truckdude239]

No the v6 4l60e is not the same it will bolt up but there are internal differances that wont hold up behind the v8s

[67-72freak]

Originally Posted by truckdude239

No the v6 4l60e is not the same it will bolt up but there are internal differances that wont hold up behind the v8s

The tranny on my 2001 4.8 silverado went out @ 150k miles (60), I replaced it with one out of a 2002 4.3 V6 (60) that had 90k.. So far my truck's odometer reads 214k and the tranny shifts as it should without any problems.

[BR3W CITY]

Originally Posted by 67-72freak

The tranny on my 2001 4.8 silverado went out @ 150k miles (60), I replaced it with one out of a 2002 4.3 V6 (60) that had 90k.. So far my truck's odometer reads 214k and the tranny shifts as it should without any problems.

Proves nothing, the 2002 4l60e was still the "ls" tranny. As I stated in the earlier post, the bolt pattern, planetaries and input shaft are different, stronger units from the vortec/sbc 60's

[smoky02]

Originally Posted by 67-72freak

The tranny on my 2001 4.8 silverado went out @ 150k miles (60), I replaced it with one out of a 2002 4.3 V6 (60) that had 90k.. So far my truck's odometer reads 214k and the tranny shifts as it should without any problems.

As long as you used the TQ converter that came from behind that 4.3 and didn't push it too hard you wouldn't have had any troubles, but I've seen one of those transmissions broken down right next to the V8 version, and there is definitely a difference in the strength of the V6 tranny vs. the V8, to point out just a few, smaller input shaft(much smaller) less clutch packs, and weaker overdrive gears. I only know this because I tried to run a V6 4L60e behind my 6.0 with a V8 TQ converter and it whined like the truck had a supercharger on it. Once I pulled it all back apart and took it to the transmission shop they actually disassembled the tranny in front of me and showed me the parts that were different.

[Andy4639]

I don't know what the motor is out of but I know when I'm at the parts house I have to tell them the 2500 series trucks (not the HD 2500) it maybe the same though. To get the right numbers for the parts with a 6.0 and 4l80 transmission. Both of which I bought together hooked together.

[informi]

Yeah, in retrospect I should have bought the transmission when I bought the motor, but I unfortunately was thinking I would just use the one I had.

So it sounds like if I can find a 4l60e from a full size truck I should be in pretty good shape.

[BR3W CITY]

...if its new enough...

[informi]

BR3W CITY, any idea how new is new enough? Thanks

[BR3W CITY]

98 is the year the input shaft size etc etc etc changed, and would be the oldest I'd look at, but I'd aim over 2000 as there were a few minor changes (the p/n switch, split bellhousing etc).

[informi]

Great. Thanks

[Ford Assassin]

If you still shopping, the 4L80e is the way to go. Much stronger than even the 'built' 4L60e's....

[informi]

I have not bought one yet. Was leaning toward the 4l60e because I believe it would match the harness and ECM I already have. Any idea what changes are required to use the 4l80e? I think BR3W City said the 4l80e has an additional VSS? Can my stock/2002 Denali ECM be flashed to support the 4l80e?

Thanks

[Ford Assassin]

Originally Posted by informi

I have not bought one yet. Was leaning toward the 4l60e because I believe it would match the harness and ECM I already have. Any idea what changes are required to use the 4l80e? I think BR3W City said the 4l80e has an additional VSS? Can my stock/2002 Denali ECM be flashed to support the 4l80e?

Thanks

Since you are going to have to have the harness modified for stand alone operation anyway, your harness guy can make the mods fairly easily. 4L80e run two sensors that are both physically VSS's, but the forward one isnt used for speed, it is used as an ISS (input speed sensor). It basically will let the PCM know if the trans is slipping.

As far as the PCM, it will need a segment swap done, but your tuner should be able to handle that when modified for the swap. Or you can find a Silverado 2500 6.0 PCM on eBay, Craigslist, etc if your tuner doesn't want to mess with the segment swap (its tuning, not physical)

[solidaxel]

If I may, I have a related question on transmissions.

How do I tell the year and is it a 4L60E or a 4l80E and what torque converter do I use with a 5.3 from a 04 Tahoe.
The yard gave me a engine and transmission, and what looks like a new torque converter.
The engine has 8 bolts and the transmission has 9 bolt holes, the top bolt hole in the engine is plugged.

Thanks, sorry for the hyjack

[Ford Assassin]

Originally Posted by solidaxel

If I may, I have a related question on transmissions.

How do I tell the year and is it a 4L60E or a 4l80E and what torque converter do I use with a 5.3 from a 04 Tahoe.
The yard gave me a engine and transmission, and what looks like a new torque converter.
The engine has 8 bolts and the transmission has 9 bolt holes, the top bolt hole in the engine is plugged.

Thanks, sorry for the hyjack

Prob best to start your own thread with pictures (more the better).

[BR3W CITY]

My 4l80e had the words "TURBO HYDRAMATIC 4L80E" in letters cast on the side of it... so I figured it was an 80e

The top bolt position on older trannies will not use the top bolt hole. Its ok this way.
iirc the 60e's only had 3 bolts from the flywheel to the converter.

[informi]

Thanks for the clarification on the harness and tuning. Just need to make some decisions I guess.