I truely can't make up my mind: PR44 or PR60

3TV said:
You guys are ruthless, LOL. Looks like I've painted myself into a corner, so to speak. I don't want people thinking I'm making things up, but I don't want to turn this thread into a thread about me either, if I post a picture of the JKs I bought. I can't win either way, so you guys tell me, ... pictures, or not? I say just drop it and move on.
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I'm not part of the original conversation, but just to throw out a standing man-rule.......

"pictures, or it didn't happen"

Just saying.....


call.
 
3TV said:
Oh, and one more thing, I used the well known JK gearing chart and looked up the engine RPM for the two Jeeps I mentioned in my first post. A 3.8 auto JK with 35s and 5.38 gears is turning 2495 RPM at 70 mph. A 3.6 auto JK with 35s and 4.56 gears is turning 2544 RPM at 70 mph. So I wasn't too far off with my seat of the pants remembering what each Jeep felt like at highway speed.
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I thought your original post said 4.56 gears on 37's...?

Regardless, if you used it and liked it that's cool for you but still not something I would recommend to others.

Dave
 
3TV said:
And I bought this 2014 JK for myself.
IMG_3751_zps281e6477.jpg


Just trying to set the record straight is all, and hopefully get off on better footing. This is not something to brag about, rather, it is something to be ashamed of. Its pretty dumb to spend this much money on Jeeps, but I've enjoyed Jeeping for 40 years now. Building a new project is what is fun to me.
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I like the looks of that last JK the best. :thumb:

You're right, it is dumb. But I hope to be able to buy my kids a nice jeep when they are old enough…if they still want them…and if gas isn't $10 a gallon. :cheesy:
 
3TV said:
Oh, and one more thing, I used the well known JK gearing chart and looked up the engine RPM for the two Jeeps I mentioned in my first post. A 3.8 auto JK with 35s and 5.38 gears is turning 2495 RPM at 70 mph. A 3.6 auto JK with 35s and 4.56 gears is turning 2544 RPM at 70 mph. So I wasn't too far off with my seat of the pants remembering what each Jeep felt like at highway speed. Except I had it wrong, the 3.6 with 4.56 gears is actually geared lower than a 3.8 with 5.38s. The difference is in the driveshaft RPM, which is way way way higher on the 3.8 with 5.38 gears. That is why they can be so hard to eliminate vibration from.

So, ... after all of this, my original point was that when choosing between a PR 44 and PR 60, I would recommend the PR 60, at least in part because of the locking hubs.
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Does this mean you can't get locking hubs with a PR 44?
 
3TV said:
Oh, and one more thing, I used the well known JK gearing chart and looked up the engine RPM for the two Jeeps I mentioned in my first post. A 3.8 auto JK with 35s and 5.38 gears is turning 2495 RPM at 70 mph.
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Well, ya got me there. I've only run 5.13's in my 3.8L JKU with an auto and running 35's but even at that, I recall running up closer to 3000 RPM at 70 MPH. I have a really hard time believing you were only seeing 2495 RPM at 70 unless you never recalibrated your speedo and your shift points were off or something.

A 3.6 auto JK with 35s and 4.56 gears is turning 2544 RPM at 70 mph. So I wasn't too far off with my seat of the pants remembering what each Jeep felt like at highway speed.
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That sounds a bit more on target but I couldn't say for sure being that I've never run 4.56 gears with 35's.

I am currently running 37" tires on my 2012 JK with a 3.6L motor and 5.38 gears. At 70 MPH, I'm turning about 3200 RPM and it SUCKS!! I used to run 5.13's with the same tires and was doing closer to 2800 RPM and to me, that was more acceptable but still on the high end. No big deal because I like the extra power it offers but the only way you're going to see your RPM's down in the 2500 range on a 3.6L motor and at 70 is with 4.88's. I suppose with 35's and 4.56, it could have similar results.

Except I had it wrong, the 3.6 with 4.56 gears is actually geared lower than a 3.8 with 5.38s. The difference is in the driveshaft RPM, which is way way way higher on the 3.8 with 5.38 gears. That is why they can be so hard to eliminate vibration from.
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WTF are you talking about?? The type of motor you have will have NO BEARING on how fast your drive shaft spins! You literally can drive your Jeep at 80 MPH, cut the motor and I guarantee you that if you have driveline vibrations, THEY WILL STILL BE THERE even with the motor off. MOST driveline vibrations come from the FRONT shaft as caster needs to take precedence. The higher the gear ratio, the faster your shaft will turn with every rotation of your TIRES. In other words, for every rotation of your FRONT TIRES make with something like 5.38 gears, your FRONT drive shaft will rotate 5.38 times and that is crazy fast! ANY balance imperfection will be amplified at this speed and that's why you have vibrations - NOT because of what motor you run. :naw:

So, ... after all of this, my original point was that when choosing between a PR 44 and PR 60, I would recommend the PR 60, at least in part because of the locking hubs.
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Really?? That's a TON of money to be spending just to have locking hubs.
 
Joker151 said:
Does this mean you can't get locking hubs with a PR 44?
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This is correct. A PR44 does not come with locking hubs but, you can buy a set of aftermarket hubs. I personally wouldn't recommend it due to their excessive cost an lack of value for that cost but, that's just me.
 
David1tontj said:
Ummmmmmm... Do you know what gears are?? It doesn't matter what engine you have, gears are gears, and 5:38 is a Lower ratio than 4:56..
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I would have to guess that the difference between the 3.8 and the 3.6 he is talking about would be related to the different transmission, which would affect rpm at certain speeds. However it would not affect drive shaft rpm.
 
wayoflife said:
This is correct. A PR44 does not come with locking hubs but, you can buy a set of aftermarket hubs. I personally wouldn't recommend it due to their excessive cost an lack of value for that cost but, that's just me.
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Does this mean they are not worth it for just the 44 or the 60 also?
 
This thread has gone so far off course people are talking about gearing of the 3.8 vs the 3.6 in a pro rock axle thread... yikes
 
Get the PR60 with all the trimmings and a few cases of beer for friends to help with the install and call it a day!
 
Are the C's on the PR44 larger than the Dana 44's? 4wd parts guy said they are the same....think he's just trying to sell my a G2 core.

Also, if I go with a PR44, do I go with a 1310 or 1350? Everything I read is saying 1350
 
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