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Tranny and t case

1119 Views 13 Replies 4 Participants Last post by  97wrangler-242
Posting here because i cant get any input from jf but anyways, I'm getting really far ahead of my self and wrapped up in all the options out there creating a build sheet I can't afford but just trying to get some ideas and I'm always ready to learn. My situation here is I'm building a 4.7 and expecting the 325-350ft lb range and way later down the road may consider a little boost. I've heard the nv3550 is the strongest of 5 speeds that bolt right up but I'm not sure how they'd hold up because most say they top out at 300ft lbs and I'm not always gentle off road. I've considered doing an sm420 and a Dana 300 flipped. Wondering if I could use my ucf ultra high skid with that combo. Also considered a Klune-v underdrive for some serious gearing options with the shorter 4 speed. There's just so many options I get confused. What do you guys think and/or have done? Also considered the nv4500 swap kit that Quadratec offers for 3600$ with a reman tranny. Is there a drive shaft that can handle the longer tranny, tummy tuck and 2.5" of lift? I already have a sye but it's not a SS. Any opinions? Just kinda up n the air on this
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One of the guys I roll with has his 2003 supercharged (by Kenne Bell, IIRC) and his NV3550 has held up to crawling, mudding, and plenty of stupid moments. I'm pretty sure between that, the slight bore, cam, exhaust, and a few other small things that he is around 360hp. Mine has held up with 270hp at the wheels. I think the same transmission was used in some of Dodge's half-tons too, FWIW.
47Hooker said:
One of the guys I roll with has his 2003 supercharged (by Kenne Bell, IIRC) and his NV3550 has held up to crawling, mudding, and plenty of stupid moments. I'm pretty sure between that, the slight bore, cam, exhaust, and a few other small things that he is around 360hp. Mine has held up with 270hp at the wheels. I think the same transmission was used in some of Dodge's half-tons too, FWIW.
I've heard of a lot of people stripping syncro's when they get rough with a little power. My ax15 is pretty much toast on the stock 4.0. Did you guys take any extra care or are they really holding up to the abuse?
97wrangler-242 said:
I've heard of a lot of people stripping syncro's when they get rough with a little power. My ax15 is pretty much toast on the stock 4.0. Did you guys take any extra care or are they really holding up to the abuse?
My ax-15 came out of the junkyard with God knows how many miles. Change out synchros and am offroadig quite alot with 33's. to me its how you use the tranny, if your gona start using the jeep like a mustang and doing launches and poppig the clutch i dont think any tranny is gona last with big grippy offfroad tires. To me its how you use it.
TJ-Q8 said:
My ax-15 came out of the junkyard with God knows how many miles. Change out synchros and am offroadig quite alot with 33's. to me its how you use the tranny, if your gona start using the jeep like a mustang and doing launches and poppig the clutch i dont think any tranny is gona last with big grippy offfroad tires. To me its how you use it.
Im going to be putting a lot more power to to it and 35s. The ax15 is not up to the task for what I will be doing
97wrangler-242 said:
Im going to be putting a lot more power to to it and 35s. The ax15 is not up to the task for what I will be doing
I think then for that you will need a built rh32.
I've heard of a lot of people stripping syncro's when they get rough with a little power. My ax15 is pretty much toast on the stock 4.0. Did you guys take any extra care or are they really holding up to the abuse?
When we put it on, we rebuilt the entire powertrain and drivetrain. We simply replaced everything inside the transmission. When we did a fluid change on his tranny a couple months ago, there was no metal on drain magnet. And on that note, he's also running an SYE with a heavier driveshaft (he had it made at a driveline shop here) and 44s with JK gears in it.

It's all about how you drive it. Just like your clutch, diffs, t-case, etc. If you're doing something that you think is going to break it/cause permanent damage, you're probably right. I just replaced all of my synchros without having as much power as him because the guy who owned it before me obviously couldn't figure out how to drive a manual. My synchro for second was shot. He told me when I bought it that even though it was stock, he proved to his buddies that he could get it where their lifted F250 Superduty's and jacked up XJs were going.

I think then for that you will need a built rh32.
And you're probably right on this one.
Well I want to put together something I can have fun in and not constantly be worried about breaking something. Isn't the rh32 an auto? I won't drive anything automatic.
You say you don't want an auto until you decide to try rock crawling. On another note, there's plenty of other 4 speeds that are good replacements for the NV3550. I'll see if I can find the list when I was considering a tranny swap. This might take awhile, though.
47Hooker said:
You say you don't want an auto until you decide to try rock crawling. On another note, there's plenty of other 4 speeds that are good replacements for the NV3550. I'll see if I can find the list when I was considering a tranny swap. This might take awhile, though.
I rock crawl with my 5 speed. Gotta b good ;)
97wrangler-242 said:
I rock crawl with my 5 speed. Gotta b good ;)
4lo and crawl ;) :thumb:
I rock crawl with my 5 speed. Gotta b good ;)
4lo and crawl ;) :thumb:
Unless you have a 4:1 or lower, then goodbye clutch. I crawl in mine, too. I got ~150k on my first while it was a DD. Now that I've been crawling, the last one ended up with ~65k.
47Hooker said:
Unless you have a 4:1 or lower, then goodbye clutch. I crawl in mine, too. I got ~150k on my first while it was a DD. Now that I've been crawling, the last one ended up with ~65k.
Mines just a toy now and it has a Centerforce so I'm not to worried about the clutch. My dad wonders why I'd rather drive my rusty old 5 speed Comanche over his 08 ford. His ford is an auto. Well, and it's a ford... Lol I just prefer a manual. Autos bore me =p
Anyone have input on the HD trannys?
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