A rebuild of #miRustyJeep...

That trim bezel turned out really nice Mike. I had no idea those things were that expensive used till you told me!

And welcome to the world of 42RLE! The OD off button is your best friend for non-hwy driving 😂
 
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Test drive this morning was a success. I’m amazed at how smooth and quiet everything is. I got it up to 60 ish and everything seems to be working as it should. Just like everyone says, OD is crazy. It engages way early, and lugs the engine. I’m also getting a bit of a flare on the 2nd to 3rd shift. The clutches engage solid though, so I’ll make sure my fluid is topped up over the next few days before I really worry about it too much.

I also managed to rebuild the transfer case properly and all my ranges work there. I can hold position in 4 low at an idle, but any amount of gas pedal will drive through them…so I will need to address that.

Gotta get insurance back on her and continue drive for a while. Need to get it all shaken down before my trip to hollerwood, ky at the end of April

765C650A-7DDD-46B1-9E76-32EF198D9095.jpeg
 
Test drive this morning was a success. I’m amazed at how smooth and quiet everything is. I got it up to 60 ish and everything seems to be working as it should. Just like everyone says, OD is crazy. It engages way early, and lugs the engine. I’m also getting a bit of a flare on the 2nd to 3rd shift. The clutches engage solid though, so I’ll make sure my fluid is topped up over the next few days before I really worry about it too much.

I also managed to rebuild the transfer case properly and all my ranges work there. I can hold position in 4 low at an idle, but any amount of gas pedal will drive through them…so I will need to address that.

Gotta get insurance back on her and continue drive for a while. Need to get it all shaken down before my trip to hollerwood, ky at the end of April

View attachment 405075

When I did my conversion it took something like 12qts of ATF before the dipstick finally read full. I just added it little by little as I drove around. I had to wait for the ATF to clear the sides of the dipstick tube each time I added more, otherwise I got inaccurate readings. It took me a couple of days before I was finally there.

Congrats on finishing the swap. It's so satisfying feeling it move under it's own power for the first time. You're gonna love it.
 
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4.88’s. I’m going to keep it for a bit to see if I need to go higher. Michigan is pretty flat.

I've only put about 50 miles on mine with the same gear and tire size. On the far Western edge of the Great Plains, I think 4.88 is perfectly wrong. It's not deep enough for the OD, and it is too deep without the OD. It's funny to think that this was the common recommendation for 20 years.
 
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The Great Salt Lake isn't even flat enough for a steady diet of those horrible gears. The wind blows there doesn't it?

I've only put about 50 miles on mine with the same gear and tire size. On the far Western edge of the Great Plains, I think 4.88 is perfectly wrong. It's not deep enough for the OD, and it is too deep without the OD. It's funny to think that this was the common recommendation for 20 years.

So, the recommendation is to go lower so that OD works around town? I drive mostly secondary roads at 55-60. I guess I’ll have to play with grim jeeper and see what’s what. Michigan is flat from a total elevation perspective, but we have lots of rolling terrain, so you won’t go very high, but you climb up and down the same 100 feet 100 times
 
These are the calculations for a brand new 35" MTR...

42rle/33.875"/4.88=2505rpm @ 75mph
42rle/33.875"/5.13=2633rpm @ 75mph
42rle/33.875"/5.38=2762rpm @ 75mph
42rle/33.875"/5.89=3023rpm @ 75mph

Where we both were with the manual transmission...

NV3550/33.875"/4.88=2832rpm @ 75mph

This was the best gearing for the tire size mine ever had with 33s...

NV3550/32"/4.88=2998rpm @ 75mph

... So, the best I can do to get back there is to go with 5.38. 5.89 can be achieved with a locker that uses standard cut gears, but that would mean new lockers on both ends for me.

And for some context, this is what the early TJ with the auto did right from the factory...

32rh/29.5"/3.73=3186rpm @ 75mph

... Which suggests that we still aren't regearing low enough if we follow the common forum recommendations. Despite the bristling I get from certain people 😉
 
These are the calculations for a brand new 35" MTR...

42rle/33.875"/4.88=2505rpm @ 75mph
42rle/33.875"/5.13=2633rpm @ 75mph
42rle/33.875"/5.38=2762rpm @ 75mph
42rle/33.875"/5.89=3023rpm @ 75mph

Where we both were with the manual transmission...
NV3550/33.875"/4.88=2832rpm @ 75mph

This was the best gearing for the tire size mine ever had with 33s...
NV3550/32"/4.88=2998rpm @ 75mph

... So, the best I can do to get back there is to go with 5.38. 5.89 can be achieved with a locker that uses standard cut gears, but that would mean new lockers on both ends for me.

And for some context, this is what the early TJ with the auto did right from the factory...
32rh/29.5"/3.73=3186rpm @ 75mph

... Which suggests that we still aren't regearing low enough if we follow the common forum recommendations.

Yeah, I was plugging in 34.3” for my tires and looking at the numbers 4.88 wasn’t low enough to begin with (and I could feel that occasionally). I’m really just going to try and deal with it for a year, so I don’t end up regearing 2x in less than a year! At least I won’t need new bearings, lol

Edit: I calculated the "true" diameter (by revs/mile) of a Brand New General Grabber X3 at 33.95" The difference at 75 between the manual (2825 rpm) and the 42RLE (2499) is 326 RPM. Doesn't sound like much, but if you calculate it by percentage, it an 11.5% reduction.

At this point the discussion is academic. I've got about 4 miles on my new set-up and not really enough to know what I don't know yet. Gears are relatively cheap though, so maybe I'll get a wild hair this summer and go to my buddy's house, who has a lift, and throw some new gears in.
 
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So, the recommendation is to go lower so that OD works around town? I drive mostly secondary roads at 55-60. I guess I’ll have to play with grim jeeper and see what’s what. Michigan is flat from a total elevation perspective, but we have lots of rolling terrain, so you won’t go very high, but you climb up and down the same 100 feet 100 times

There are two schools of thought on that. Bring the gearing to a level that would let you run OD around town or set it up so that you can shut off the OD running up hills in 3rd or Drive. You would run the calculator to wind up around 3200ish RPM at around 60-65 mph or so.

Both of those have serious flaws due to the terrible .69 OD ratio, it is just too far from 1-1 in drive to make either school of thought work that well.
 
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Yeah, I was plugging in 34.3” for my tires and looking at the numbers 4.88 wasn’t low enough to begin with (and I could feel that occasionally). I’m really just going to try and deal with it for a year, so I don’t end up regearing 2x in less than a year! At least I won’t need new bearings, lol

Edit: I calculated the "true" diameter (by revs/mile) of a Brand New General Grabber X3 at 33.95" The difference at 75 between the manual (2825 rpm) and the 42RLE (2499) is 326 RPM. Doesn't sound like much, but if you calculate it by percentage, it an 11.5% reduction.

At this point the discussion is academic. I've got about 4 miles on my new set-up and not really enough to know what I don't know yet. Gears are relatively cheap though, so maybe I'll get a wild hair this summer and go to my buddy's house, who has a lift, and throw some new gears in.

The easiest way for me is to take it for a drive and get a steady speed around 65 or so and get the RPM as close as I can. Then plug those into the calculator and change the tire size until the calculator matches my dash numbers. (assuming you have corrected the speedo)
 
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The easiest way for me is to take it for a drive and get a steady speed around 65 or so and get the RPM as close as I can. Then plug those into the calculator and change the tire size until the calculator matches my dash numbers. (assuming you have corrected the speedo)

I use Technology to do the same thing...GPS speed and Data out from the OBD port for RPM. I'll do that eventually, but we all know where this is going...
 
I'm slightly ecstatic right now. Just returned from a test drive after doing my transmission quick learn, and having one troublesome tire balanced (took em 5 times of breaking the bead and rotating to get it to a road force solution). The Jeep has never driven so well. I guess I can't say never because I got it with 126,000 miles, but since I've bought it, it's never been this good. It was FACTORY when I bought it too. No mods.

The transmission quick learn was necessary. It fixed all the hard shifting I was getting. It shifts like butter now. I bought a 120 dollar "dongle" from Amazon that had the function and I'm so glad I did. Took a chance, as it had free returns and the stealership wanted 170 dollars to do it! It was less than 30 seconds to do. Unbelievable.

This is the scanner I got. Runs on your cell phone through Bluetooth —->DONGLE<—-

Now...this project is DONE. On to the next one...Not sure what its going to be yet. Lights probably, but maybe some corner armor. I gotta see if I can get some 6061 remnants somewhere. I'm not paying 1000 bucks for premade corner armor.
 
I'm slightly ecstatic right now. Just returned from a test drive after doing my transmission quick learn, and having one troublesome tire balanced (took em 5 times of breaking the bead and rotating to get it to a road force solution). The Jeep has never driven so well. I guess I can't say never because I got it with 126,000 miles, but since I've bought it, it's never been this good. It was FACTORY when I bought it too. No mods.

The transmission quick learn was necessary. It fixed all the hard shifting I was getting. It shifts like butter now. I bought a 120 dollar "dongle" from Amazon that had the function and I'm so glad I did. Took a chance, as it had free returns and the stealership wanted 170 dollars to do it! It was less than 30 seconds to do. Unbelievable.

This is the scanner I got. Runs on your cell phone through Bluetooth —->DONGLE<—-

Now...this project is DONE. On to the next one...Not sure what its going to be yet. Lights probably, but maybe some corner armor. I gotta see if I can get some 6061 remnants somewhere. I'm not paying 1000 bucks for premade corner armor.

I'm coming up on a year from my swap and I share the exact same sentiments you just listed. Congrats on getting it done!

What's sad is people get in the jeep and don't even know it was a manual. Yes, that's the point, but dammit I worked hard on this! :ROFLMAO: