What Manual Transmission for an LS Swap?

Munchie

Munchie

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The Colony, Texas
I’m looking to swap a 5.3 Vortec V8 into my 98 Jeep Tj before I get out of high school. I almost have the funds but I just cant seem to find a good manual transmission option!! I thought about the SM465 but I need something good for highway speeds and I considered the TR5 but i need something with a low gear in 1st for crawling. I also considered the NV4500 but it seemed very expensive and hard to source. Do yall have any suggestions>
 
Munchie said:
I’m looking to swap a 5.3 Vortec V8 into my 98 Jeep Tj before I get out of high school. I almost have the funds but I just cant seem to find a good manual transmission option!! I thought about the SM465 but I need something good for highway speeds and I considered the TR5 but i need something with a low gear in 1st for crawling. I also considered the NV4500 but it seemed very expensive and hard to source. Do yall have any suggestions>
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In my opinion there isn't a great choice for a manual..is there a reason you aren't interested in an auto?
 
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Getrag 238 if you can find an adapter. Or look for something called the Trazilla. IIRC it's a T56 setup for 4wd.
 
P man said:
In my opinion there isn't a great choice for a manual..is there a reason you aren't interested in an auto?
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X2. I'd have obviously suffered a mental collapse if I went with a manual transmission with that conversion.

@Munchie I thought I needed a manual transmission for offroading with my first TJ so that's what I bought. That ended up to have been the wrong decision and I later converted it to an automatic which transformed it into a trail beast.
 
The problem with most, if not all, light duty manual transmissions designed in the last 50 years or so is that they aren't geared low enough - and frankly, don't have enough gears. SM-420 and the "almost as good" SM-465 are old to ancient designs - they have the gearing, but they don't have the number of gears that are optimum. An SM-420 with a splitter of one sort or another would be wonderful - but good luck fitting that into a Jeep. Anything can be done of course, how much to you wanna spend?

I don't like automatics - they're boring as hell and not as reliable as a manual all other things being equal. But with that said, with the lack of gearing in manuals, autos rule. Sucks, but that's the way of it. Nobody wants to design a "good" manual any more - although perhaps the one in the new Bronco is an exception?

I had an '87 F-250 diesel with the 4 speed. It drove "ok" - but it really needed a deeper 1st and more gears spaced closer together. The 5 speed Ford came out with a year or two later wasn't any better as the 5th was just an OD - which is OK, but didn't do anything about the other issues. I was going to install a splitter on it, but then we got out of RV ownership, so I sold it in Y2K and bought the Mercedes which I still have. I really did love that truck though.
 
The AX15 is your best bet for a manual transmission if you want a overdrive transmission. If not then the SM465 would be great.
What are you looking for in a manual transmission? You really haven't said what criteria you are using in choosing a transmission.
I need to find the link for another 5 speed that was just talked about.
It's about $6k for it and all the needed parts.

Edit:
The TR-4050 listed above was the transmission I was thinking of.
 
Munchie said:
I have the AX-15 now behind my 2.5 but its having problems even behind that anemic thing so I don‘t know about mating it with an LS
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Unless someone swapped a AX15 in behind your 2.5 then you have a AX5 not AX15.

And AX15 is rated for 300+ HP & TQ so unless you are planning on running a hopped up 5.3 a AX15 is more than adequate.

https://www.novak-adapt.com/knowledge/transmissions/manual/ax15/

Novak also sells an IMPROVED version that is suppose to be stronger.

https://www.novak-adapt.com/catalog/transmission/transmission-packages/ax15-package/
Advance Adapters supports it's use also.

https://www.advanceadapters.com/products/26-ax15--aisin-ax15-5-speed-transmission-new/
 
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Wildman said:
The AX15 is your best bet for a manual transmission if you want a overdrive transmission. If not then the SM465 would be great.
What are you looking for in a manual transmission? You really haven't said what criteria you are using in choosing a transmission.
I need to find the link for another 5 speed that was just talked about.
It's about $6k for it and all the needed parts.

Edit:
The TR-4050 listed above was the transmission I was thinking of.
Click to expand...
My criteria is just something that will handle a 5.3 LS engine, have a good low end, and get me going 70 on the highway comfortably.
I was looking at the TR-4050 but isn't the shifter in those a little too far back?
Wildman said:
Unless someone swapped a AX15 in behind your 2.5 then you have a AX5 not AX15.

And AX15 is rated for 300+ HP & TQ so unless you are planning on running a hopped up 5.3 a AX15 is more than adequate.

https://www.novak-adapt.com/knowledge/transmissions/manual/ax15/

Novak also sells an IMPROVED version that is suppose to be stronger.

https://www.novak-adapt.com/catalog/transmission/transmission-packages/ax15-package/
Advance Adapters supports it's use also.

https://www.advanceadapters.com/products/26-ax15--aisin-ax15-5-speed-transmission-new/
Click to expand...
Thank you! I was definitely mistaken. I do that the AX5. I'll start looking into the AX15. Thanks for all the links too!
 
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Munchie said:
My criteria is just something that will handle a 5.3 LS engine, have a good low end, and get me going 70 on the highway comfortably.
I was looking at the TR-4050 but isn't the shifter in those a little too far back?

Thank you! I was definitely mistaken. I do that the AX5. I'll start looking into the AX15. Thanks for all the links too!
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If you are going thru the process of a engine swap why would where the transmission shifter come out at matter? You cut a hole if needed and that is where the shifter sits.

Doing an engine swap isn't plug and play and since you are starting with a 4 cyl engine the Holley swap mounts don't just drop in like they do if you had a 6 cyl.

https://shiftsst.com/1997-2006-jeep-tj
Here is a thread with someone doing a LS swap with the TR4050.

https://wranglertjforum.com/threads/tremec-tr-4050-transmission-swap-kits.24764/#post-960402
Need to do some searching and reading. You do know you'll need a new transfer case or the input gear for your transfer case? A 4 cyl has a 21 spline input gear and you'll need a 23 spline input gear for most transmission you'd want to put behind a LS either manual or automatic.

Try reading some of the build threads on here with engine swaps.

And not that I'm against a GM engine in a Jeep but why a LS swap over a Dodge V-8? Yes I know the LS get better fuel mileage and makes more power easier but I'm just asking? What is your swap budget? Any other mods planned during the engine swap?
Why are you doing the engine swap?
 
Wildman said:
If you are going thru the process of a engine swap why would where the transmission shifter come out at matter? You cut a hole if needed and that is where the shifter sits.

Doing an engine swap isn't plug and play and since you are starting with a 4 cyl engine the Holley swap mounts don't just drop in like they do if you had a 6 cyl.

https://shiftsst.com/1997-2006-jeep-tj
Here is a thread with someone doing a LS swap with the TR4050.

https://wranglertjforum.com/threads/tremec-tr-4050-transmission-swap-kits.24764/#post-960402
Need to do some searching and reading. You do know you'll need a new transfer case or the input gear for your transfer case? A 4 cyl has a 21 spline input gear and you'll need a 23 spline input gear for most transmission you'd want to put behind a LS either manual or automatic.

Try reading some of the build threads on here with engine swaps.

And not that I'm against a GM engine in a Jeep but why a LS swap over a Dodge V-8? Yes I know the LS get better fuel mileage and makes more power easier but I'm just asking? What is your swap budget? Any other mods planned during the engine swap?
Why are you doing the engine swap?
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I'm considering throwing a Dana 300 behind the transmission, which I know will require adaptation, so I can do a twin stick setup.

My budget is around 10 grand and I really only plan on doing the engine, transmission, transfercase, and driveshafts during the swap.
Later I'll be throwing in G2 axels and some other stuff here and there but the 10 grand is going towards the swap.
 
A manual transmission may be more fun, at least at times, but I'd sure reconsider going with an automatic if you want it to be a trail beast too.
 
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