6 speed Auto conversion

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mattt

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Yeah the price is a huge shocker. I am hoping as more people figure out the electronics side of the transmission, the controllers will start to come down in price.

I agree with him on everything except the 60e part. Before I spent any money on a 60e, I would swap in an 80e instead. The upfront labor IMO pays off in the end of never having to worry about even a built transmission failing.
I could see the price adjusting as more figure out the electronics side of things over time.

I see your point that a 4L80e is more stout than a 4L60e, but for a 2004 Tahoe, I don't think the 4L80e is the right transmission. My factory trans is currently at 333k mileage, so they can be made to last with proper care. The plan is to do some upgrades, and hopefully swap internals to turn it into a 4L65e. Not sure what upgrades yet as that's to be determined for what's hopefully another 300k transmission ;)

I have driven 2 different 4L80e's in 2500HD trucks I used to own and I was never jazzed up with how they shifted, and the gearing spread.
 

Mudsport96

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I could see the price adjusting as more figure out the electronics side of things over time.

I see your point that a 4L80e is more stout than a 4L60e, but for a 2004 Tahoe, I don't think the 4L80e is the right transmission. My factory trans is currently at 333k mileage, so they can be made to last with proper care. The plan is to do some upgrades, and hopefully swap internals to turn it into a 4L65e. Not sure what upgrades yet as that's to be determined for what's hopefully another 300k transmission ;)

I have driven 2 different 4L80e's in 2500HD trucks I used to own and I was never jazzed up with how they shifted, and the gearing spread.
The gearing spread is better than the 60e. The problem is 1st isnt as steep so it makes an already underpowered tahoe feel even more sluggish because you get less of an rpm drop on the 1-2. A good converter would fix that. As for the shifts a transgo hd2 kit fixes that as well.
If you were looking for a middle ground upgrade, im 76.34% sure a 4l70e drops in place of a 60 and 65e. Think its just a repin of a few wires, and leave the input speed sensor unplugged since a vehicle with a 60/65e wouldnt look for it anyways.
Supposedly a stronger case design and beefier internals but same outside dimensions.
 

TollKeeper

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The gearing spread is better than the 60e. The problem is 1st isnt as steep so it makes an already underpowered tahoe feel even more sluggish because you get less of an rpm drop on the 1-2. A good converter would fix that. As for the shifts a transgo hd2 kit fixes that as well.
If you were looking for a middle ground upgrade, im 76.34% sure a 4l70e drops in place of a 60 and 65e. Think its just a repin of a few wires, and leave the input speed sensor unplugged since a vehicle with a 60/65e wouldnt look for it anyways.
Supposedly a stronger case design and beefier internals but same outside dimensions.
Your not the first person I have heard about the 4L70 being a almost direct swap. I -think- PCMofNC even makes a adapter plug, to make it plug and play.
 
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mattt

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Been researching this 4l70 v 4l65 and I'm not seeing much difference in them. Same gear ratios, and mostly the same internals, with some minor differences. The electrical differences are as described with the ISS being in the 70 and not necessary when used in place of a 4l60 or 4l65. Looking around for a 4l70 for sale and they are few and far between. Can anyone else make the case for going 4l70 vs the 4l65? Thanks.
 

swathdiver

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Been researching this 4l70 v 4l65 and I'm not seeing much difference in them. Same gear ratios, and mostly the same internals, with some minor differences. The electrical differences are as described with the ISS being in the 70 and not necessary when used in place of a 4l60 or 4l65. Looking around for a 4l70 for sale and they are few and far between. Can anyone else make the case for going 4l70 vs the 4l65? Thanks.
The 4L70 Supermatics were used behind the 2007-2009 6.0 motors in the half ton pickups and behind the Avalanche and Suburban 6.0 L76s in 2007-2008.

They are more stout than a 4L60/4L65 but these can be built to handle plenty of horsepower. It is not necessary to swap out a 4L60/4L65 to a 4L70 when more strength is desired as all of those features can be retrofitted.

 
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