8HP70 and 4.0?

[Wildman]

View: https://youtu.be/AL9ptuvK0xY?si=iQ5B9E9KChPP9zgi

 

[Strizzo]

As Rasband said yes you'll need a a new crossmember. But as stated in the first post the 8HP70 is shorter than the 42RLE... Which suggested the need for a new crossmember already. This would be a good time to add a separate crossmember anyhow. Makes dropping your skid plate a LOT easier.
Now if you've still got the stock shovel I'm sure some sort of mount could be fab to work with it.

Is the 8HP shorter than the 42RLE overall, or shorter than the 42RLE plus the spacer plate between the transmission and transfer case?

 

[Wildman]

Is the 8HP shorter than the 42RLE overall, or shorter than the 42RLE plus the spacer plate between the transmission and transfer case?

I have no idea... American Iron the company who is working on this project is the one who said it's shorter....

I've got a 8HP70 sitting in my garage. I've measured it a few times and posted the lengths in a few other threads.

This is what AI says:

The Chrysler/Jeep 42RLE 4-speed automatic transmission has an overall length of 33 inches (2.75 feet).
Keep in mind that this measurement applies to the base transmission case. If you are accounting for the 4WD version (which connects to a transfer case), it will add roughly another 1.3 feet (15 to 16 inches) to the total powertrain assembly.

So that would mean with the 4WD plate it's 48" long which is HUGE IMO.... Never knew this... Wonder if someone with a 42RLE could confirm or not???

And AI says about the 8HP70:

A 4WD/AWD ZF 8HP70 8-speed automatic transmission has an overall case length of approximately 27.25 inches (about 692 mm) from the bellhousing face to the end of the transfer case/tail housing. The main transmission case itself measures roughly 23.75 inches (603 mm), with the 4WD extension/tail housing adding another 3.5 inches (89 mm).
For your convenience, here are the core dimensional specs for a 4WD 8HP70:

• • Overall Length: ~27.25 inches (692 mm)
  • Case Length: ~23.75 inches (603 mm)
  • Bellhousing Width: ~14.17 inches (360 mm)
  • Main Case Width: ~9.84 inches (250 mm)
  • Dry Weight: ~192 - 200 lbs depending on fluid/converter
  • Torque Capacity: Up to 700 Nm (516 lb-ft)

I'll be heading out to the garage in a while and will get the length from the one I have in my garage. And this will be from face of bellousing to end of 4WD adapter. But off the top of my head I seem to remember it being around 32.75" long.

EDIT: 27.75" OAL on the one I have.

 

[B00mb00m]

View: https://youtu.be/WNeBQq0JYPA?is=7vA601ix7sZgSPwP

Here’s a taco doing the swap. He runs the shift control without any torque management from the engine, he says the power is low enough it shifts great.

 

[Hackyman]

Maybe dumb question but isnt this company planning to sell a complete kit with a mopar crate trans? Quick Google search makes it seem like a $10k transmission. Is in the realm of reality?

 

[GoldenGorilla]

Quick Google search makes it seem like a $10k transmission. Is in the realm of reality?

Just Empty Every Pocket

 

[bbaldwin237]

Maybe dumb question but isnt this company planning to sell a complete kit with a mopar crate trans? Quick Google search makes it seem like a $10k transmission. Is in the realm of reality?

They were asking and it seemed like the general consensus was that it was likely the kit may be offered both ways.

 

[Hackyman]

They were asking and it seemed like the general consensus was that it was likely the kit may be offered both ways.

I guess I read the comments totally different and gathered that they didn't want to deal with problems and preferred to drop ship a transmission to you from mopar.

Maybe somebody is dropping $12k in transmission into a TJ, but even as a guy who loves to waste money that seems crazy.

 

[bbaldwin237]

I guess I read the comments totally different and gathered that they didn't want to deal with problems and preferred to drop ship a transmission to you from mopar.

Maybe somebody is dropping $12k in transmission into a TJ, but even as a guy who loves to waste money that seems crazy.

It might have been somewhere else that I was reading it, or a video. But that was the impression I got from it.

 

[Irun]

Maybe somebody is dropping $12k in transmission into a TJ, but even as a guy who loves to waste money that seems crazy.

Only way I'd do that is if there was a Hemi attached to the transmission!

 

[B00mb00m]

It definitely sounded like the owner wanted to drop ship a trans which makes sense from a product support perspective. It is quite the price pill to swallow but if it completely changes the driving experience so as to not require a v8 to go up hill at 55mph with 37s then some will buy. I’d much rather try to find a low mile used transmission. There are so many configs of the 8HP70 you’ll have to be careful about the source.

 

[jjvw]

It definitely sounded like the owner wanted to drop ship a trans which makes sense from a product support perspective. It is quite the price pill to swallow but if it completely changes the driving experience so as to not require a v8 to go up hill at 55mph with 37s then some will buy. I’d much rather try to find a low mile used transmission. There are so many configs of the 8HP70 you’ll have to be careful about the source.

I still come at this as it being something to consider when an existing 42rle dies and needs to be replaced. The costs of that go a long way towards a used 8hp70 and the end result is a much nicer transmission.

 

[Wildman]

Something else to consider here...
If American Iron decides to offer just the adapter and you have NO plans to ever do a V-8 swap you could get away with a 8HP45 or 8HP55 transmission over the 8HP70... Now I don't know if they are any cheaper or more or less available but it's just an idea...

 

[mrblaine]

I still come at this as it being something to consider when an existing 42rle dies and needs to be replaced. The costs of that go a long way towards a used 8hp70 and the end result is a much nicer transmission.

Or maybe we could stop depending on a transmission to try and overcome our fucked up gearing.

 

[jjvw]

Or maybe we could stop depending on a transmission to try and overcome our fucked up gearing.

I forget that there is a obstinate contingency that will do everything short of regearing the axles to suit the realities of the transmission. And after that, these same people will hobble the transmision to prove some point.

 

[Irun]

I'll maybe get beat up on, but who cares. The 42RLE just plain gets a bad rap. Once the Jeep is re-geared, besides the .69 overdrive, the 42RLE is a rock-solid transmission. They last a long time, run relatively cool, and are dependable for wheeling. If they weren't, so many people wouldn't be converting to them. I've put more than 400,000 miles on 42RLEs and the only bad experience I've ever had was a 42RLE in a 2011 JKUR. That's a story on its own!

 

[jjvw]

I'll maybe get beat up on, but who cares. The 42RLE just plain gets a bad rap. Once the Jeep is re-geared, besides the .69 overdrive, the 42RLE is a rock-solid transmission. They last a long time, run relatively cool, and are dependable for wheeling. If they weren't, so many people wouldn't be converting to them. I've put more than 400,000 miles on 42RLEs and the only bad experience I've ever had was a 42RLE in a 2011 JKUR. That's a story on its own!

Most of the irritating behaviors of the 42rle go away after it gets enough axle gearing. The bigger irritation is that people still fight doing that 25 years later.

 

[5632]

Why do Jeepers need 8 speed transmissions? 5 of the gears are overdrive.

 

[jjvw]

Why do Jeepers need 8 speed transmissions? 5 of the gears are overdrive.

5 overdrive gears? Prove it.

 

[mrblaine]

Why do Jeepers need 8 speed transmissions? 5 of the gears are overdrive.

Go drive a Ford Transit Connect cargo van and then get back to me.