How hard is it to replace a 42RLE automatic transmission?

explorerlyon

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I am trying to decide to replace my transmission myself with a remanufacture/rebuilt one (42RLE). Having never pulled a transmission before, is it worth attempting? Anyone regret trying it themselves? How many hours for a first timer? Or, is this one of those things that if you don't have a lot of experience with transmissions don't DIY?
 
A shop could do it in probably 3-6 hours.

Doing it yourself for the first time, it's going to take you probably a weekend.

You'll need to have a transmission jack, possible a spare set of hands, and a lot of patience the first time. Personally I'd rather just pay a shop, as working on your back under the vehicle isn't the same as having a lift.
 
I am trying to decide to replace my transmission myself with a remanufacture/rebuilt one (42RLE). Having never pulled a transmission before, is it worth attempting? Anyone regret trying it themselves? How many hours for a first timer? Or, is this one of those things that if you don't have a lot of experience with transmissions don't DIY?
It isn't that hard, tedious if you are unfamiliar and you need to have your wits about you, but difficulty lies in just solving the puzzle. There are lots of things that we can help you with and you are always welcome to call anytime as you know.
I suggest a set or at least a pair of drive on ramps to get room to work under the rig.
Don't run over yourself.
Stand the trans up on end to seat the torque convertor.
Get a new or reman torque converter.
Get a set of E-torx sockets.
Get enough extensions to reach from back of trans to back of motor.
Do pull t-case.
Drain trans before you start.
Beg, borrow, or steal a trans jack. Come get mine if you need one if you are doing this in SoCal.
 
With those ramps, do you still have to be on your back, or is there enough room to at least sit up?
You can make your own if you want. These were about $20 worth of 2x12 and Home Depot cut all the lengths I needed for nothing. Just screwed them all together at my house. These were for a low profile car.

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It's not a bad job, just pay attention to the helpful hints provided by Blaine. It's a PITA and not easy but it's not something to be afraid of either. Just carefully mentally note how everything came apart and it should go fine.

I do strongly recommend renting or buying a transmission jack like Harbor Freight sells inexpensively. That's what I used the several times I had to pull my transmissions and they're really helpful, not so a standard floor jack.

And keep this in mind... the transmission will seem like it is not going back into place if you're even a RCH off on its angle where it slides back into the engine. Just being a degree or two off will make it seem like there's something in the way. Sometimes it just needs the slightest amount of additional or less height on the jack to make it slide in easily the rest of the way.

Last thing... do NOT use the transmission mounting bolts to try to pull the transmission the rest of the way into place against the engine if it's not going in easily. It's too easy to strip or break a bolt hole on the engine which can be catastrophic.
 
One more thing, you don’t want to get your vehicle higher than your transmission jack can reach.

That makes sense. I keep thinking of lifts and the big support stands they use for the transmission in that case.
 
To play the devils advocate I'd think hard before attempting this if you aren't a somewhat experienced mechanic. I don't mean shop expereince but you should know your way aroud a wrench. It doesn't take any transmission specific experence but that doesn't mean it doesn't take some expereince. I wouldn't recommend an inexperienced mechaninc tackle this sort of thing alone and help from the internet isn't going to help when you are sturuggleing to figure out how to remove your hand from between the tub and the transfer case. You can get hurt, you can damage expensive stuff. I really have no idea where you are coming from experience wise but if you are green, you might think twice. If you're not so green you'll be fine but part of me doesn't see a not so green mechanic coming on the internet and asking for advice about what is essentially removing a few bolts and taking a hunk of metal out of the Jeep.
 
It isn't that hard, tedious if you are unfamiliar and you need to have your wits about you, but difficulty lies in just solving the puzzle. ...
I suggest a set or at least a pair of drive on ramps to get room to work under the rig.
Get a set of E-torx sockets.
Thank for you help, I appreciate it. With the ramps, are you just lifting the front end up then rather than lifting entire rig onto jack stands? I have more E-torx than I know what to do with now. The last couple years I have been working on a Porsche and BMW I purchased for fix up. Every freaking bolt is an aluminum Torx that has to be replaced every time due to torque-to-yield (stretches). :)

I really have no idea where you are coming from experience wise but if you are green, you might think twice. If you're not so green you'll be fine but part of me doesn't see a not so green mechanic coming on the internet and asking for advice about what is essentially removing a few bolts and taking a hunk of metal out of the Jeep.
I understand what you are saying. I have the mechanical aptitude for the job. But, I have also realized some jobs are best left to professionals as experience matters sometimes or special tools not worth purchasing.
 
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I was in your situation, and with a teenage son and access to a lift at a friend's body shop, we got it done in a day. We have a 5spd so we replaced the clutch too. I thought it would be a good idea to get the rear main seal done too while it was on the lift. It would have been better to leave that for another day.