chuck45

The motor and trans are out of a 2013 Denali XL that rolled off of a vehicle transporter when being delivered to the dealer. The assembly has 2 miles so is essentially new. The freight company delivered the engine and tranny this past week. I have a few more weeks to wait for the install kit but am going to start doing some preliminary things.

One of my first orders of business is to deal with the transfer case issue. The output shaft of the GM 6L80 transmission is too large to mate with the input on the Rubi 241OR 4:1 Transfer Case. The solution is to use an Atlas or to use a 241J (std non-Rubi 2.72:1 TC) and replace the front input gear of the TC. There is no adaptor that will work on the 241OR. I have decided to go with the 241J non-Rubi TC and so I'm looking for a TC. I am willing to buy one outright or to arrange a swap of my Rubi TC for your no-Rubi TC. I can buy a 241J for 450 and then sell mine or we can swap. 241J's seem to be worth about 450 (I know where three are for that price with 9k, 12k and 17k miles) and are in little demand. Rubi TC's seem to go for 1200 to 1500. I am willing to swap TC's for your TC and 600 cash.

I am in Grand Junction, Colorado so somebody in Colorado or Utah would be best, though I get down to NM quite a bit. If nothing local can be arranged we could do something with a freight company. My 6.2/6L80 weighed 789 pounds and shipping from Michigan to CO was 450. I understand the 241 TC's weigh about 150 pounds and and it would be a lot smaller than the 6 ft by 3 ft pallet the engine came on.

I drove a JK with the conversion already done and I can tell you that it totally transforms the JK into a much better machine. The difference is unbelievable. It is so calm and capable. During the test drive we were climbing a grade at 50 MPH. My JK (37's and 5.13's with an auto) would have been in 2nd gear and high revs. The 6.2 was in Cruise Control, maintaing speed perfectly - in 6th gear at 1100 RPM!

We went down a steep hill, on pavement, in the 6.2. In 2Hi and 1st gear it went slower than my Rubi would have in 1st gear and 4 LOW. The 6.2 is a great engine, far superior to the Hemi, but the secret weapon in the conversion is the 6L80 transmission. It is a class act, always seems to know what gear it should be in, has a 4:1 first gear ratio and has a low percentage of power loss compared to normal automatics.

FWIW we rented a 2013 4 DR Wrangler to finish a trip with some friends (when our JK had a catastrophic front axle failure) and drove it from Ouray to Durango CO over Red Mountain. The new 3.6 engine is a POS. It did no better than my heavy laden JK with 3.8 if my JK was in a gear it was happy in. The rental JK was a soft top with no rear windows installed, no bumpers and no carpet; in other words the lightest 4 DR JK you'll ever find. To maintain 50 MPH over Red Mtn it took 3rd gear and 5000 rpm. The only good thing about it was the 5 speed transmission. I think the real world performance would have been better if they stuck this transmission behind the 3.8 instead of the 3.6. The 3.6 is all numbers and nothing but a high RPM screamer. Bad move on Jeeps part.

mstrofpuppets

How is this engine better than a Hemi conversion? I ask because I don't know and am looking at doing a 5.7 Hemi with a manual trans in my JKUR(which is already a manual). Thanks and good luck with the build. Post up some pics for sure.

williard86

Hmm...I'd swap t cases with you but I'm in Alabama. I'm subscribing though!

renegade4x4

The 2013 jeep you rented probably had the crappy 3.21 gears in it. Mine was down shifting like crazy on small inclines with these gears and I live in Florida. The 3.73 gears or more are a perfect companion to the 3.6, full load no downshifting at all even on moderate grades doing 70. Nothing like a Hemi or LS3 though.

Scrapin' Metal

I must be missing something. My stock auto 3.6 runs 80mph at about 2900 rpm's and never down shifts. I too live in Florida. Maybe it has 3.73's and the window sticker is wrong??

renegade4x4

You would have to have 4.10s to run that high of rpm in 5th gear. Or your still in 4th with 3.21s and it wont up-shift. When I had my 3.21s there were times it wouldn't up shift to 5th because of 4th working to hard.

williard86

if you don't mind me asking, how much does a motor and trans like that cost?

JKinMA

Before I offer anything, I ask for a clarification. What you're requesting is swapping your Rubi 4:1 TC for our non rubi 2.72:1?

project06tj

Well I strongly disagree with you about the 3.6L being garbage. You say it is "all numbers" and it is. But isn't every engine ever produced all about the numbers?


Here's the "numbers"




They don't lie and they are better vs the 3.8L in every possible way. An excellent move on Jeeps part.
In my personal experience, you can feel the torque when it starts coming in around 1,700 RPMS. It makes a difference.


However I am interested in your build. Where did you find the donor engine? Was it expensive?

OJK12

I totally agree I had a TJ with the 4.0 and when I started looking at the JK's and test drove the 3.8 I was very disappointed and figured I'd never trade my TJ but all that changed when my buddy got one of the first 3.6 powered grand Cherokees and I was hooked it still lacks the low end hit the pushrod engines have but excels at high RPM and I believe this will be another long lasting jeep engine, or at least till new CAFE laws prohibit it.