4L65E Conversion

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#1taho

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I have a buddy that has a 2000 taho. the tranny has just went and he wants to put in a 4L65E in place of the 4L60E. from what I can see they are exactly the same and it has two extra pins that the wiring harness wont use(I think its for the speed sensor). If I am wrong or missing something can someone tell me if it is possible to do this conversion,and what will need to be changed in order to make this work. and is it worth it?
 

Big Buttons

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If you are going to swap the trans, swap to a 4L80e. The 65e is not much more powerful than the 60e.
 
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#1taho

#1taho

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Its a money thing for him. he found a good used 4L65E cheep with low km. The 4L65 will be fine for haw he drives too. "grandpa driver" :boti:

So is it an easy swap?

Pic's of his truck will follow
 

Big Buttons

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If his current transmission isn't going out now or doesn't have high KM then I would just do the Transgo HD2 shift kit, corvette servo and billet 4th gear servo with billet cover. And a bigger transmission cooler with thermal bypass since you live in Canada.
 
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#1taho

#1taho

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His truck has 330800 km so it has "high K". unfortunately it has to be done. it won't move at all any more. third started to slip once and a while and reverse started to slip. then coming down the High way last week it started to slip in overdrive, third and then that was it, it wouldn't go anymore. the one change I told him to do was a corvette servo to help firm up the squishy shifts.
 

TheAutumnWind

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If his current transmission isn't going out now or doesn't have high KM then I would just do the Transgo HD2 shift kit, corvette servo and billet 4th gear servo with billet cover. And a bigger transmission cooler with thermal bypass since you live in Canada.

You really think that billet 4th gear servo is worth it huh?

I'd definitely atleast do vette servo and transmission cooler. Might as well install some sort of shift kit or line pressure booster to help with longevity.

What year is the 4l65e? The only difference that I am aware of would be the 5 pinion planetary gears IIRC. It's not really much stronger than the 4l60e, but it should be a very simple swap. The extra pins in the harness may be for the transmission temp sensor I'd guess.
 
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#1taho

#1taho

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Does it work ?????

The tranny we found is out of a 2002 Denali. under 200km. I am only concerned about the wiring of the pins. from all I can see the tranny's are exactly the same. but I can't find a good guy that's in my area that knows. I talked to two differnt tranny shops, two parts guys and three wrecking yards. no one had a clue!!! So I am turning to you guys I haven't been steered wrong yet. I Know the 4L65E in not much better than th 60 but In his case that's all he can afford,and will be a good enough up grade for him.

It was mentioned 4L80E. So what is involved in changing 4L60 to a 4l80 ???
cross member for sure and I think I would have to change the pins around on the plug. Will the transfer case fit the 4l80 and will the drive shafts fit?
I don't think they don't.
 

jough

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From what I understand, the 4L65E came about due to the 6.0 engine exceeding the torque rating for the 4L60E, which is behind 4.8 & 5.3 engines. I also understand that most of the strength upgrades to the 4L65E were eventually incorporated into the 4L60E. However, I don't know exactly when those 4L60E upgrades happened. By 2004-2006, I think either transmission was plug & play behind a 5.3 or 6.0 & harness.
 
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#1taho

#1taho

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Thanks for the help

Pulling out the transmission next week. I will find out for sure then. In the mean time if anyone knows for sure or anything extra I have to do, the intell is greatly appreciated. and when the job is done I will leave an up date on what was done to make it work.:Good or Bad:
 

Big Buttons

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You really think that billet 4th gear servo is worth it huh?

Yes it is worth it. These 4L60e/65e transmissions blow up under a good amount of power.

I have the tru cool 40K, both servos, and it is tuned for faster shifting and line pressure is boosted. My 1st gear just started slipping when I load it on my converter about 2 months ago at 106K miles. But I drive very hard.
 

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