StevenH

No, this guy :waving:

I was taking him serious as hardcore until I seen the slipknot shirt :D

That will make you go blind :D

I was going to do a doubler but everybody says it won't go under the stock floorboard. Have you looked into this or are you planning on cutting the floor?

That's a good idea, I might do the same thing

Nice!

Would that writeup be Comanche specific enough to be here? or is it so easy it doesnt require a writeup? I was about to start it and decided to hold off...

The frontend was that much for sure. I don't know if anything broke or not, it looked like it took the landing really well. I will set up the jump, who wants to try it? :D

With a larger spline count, the shaft is thinner than stock.. here's a side shot and it shows there is still plenty of material left.

You unbolt the input housing off of the d300, remove the snapring, remove the gear, remove the next snapring and the shaft and bearing comes right out. 15 minute job w/taking pictures. This will be my first project writeup and I took plenty of pictures :cheers:

I see I'm not the only jumper here. I told that on another forum before and nobody believed it. Hell I jumped so far that I didn't believe it :D

So I can sleep good at night knowing I will never have to worry about my tranny breaking I have killed a TH400 with an Iron Duke in front of it. Of course it had a turbo and NO2! LOL! How much HP were you putting out? And who built the transmission, you got your money back I hope :D

It's a shame we can't cut off more than that from the rear, but that's the same thing I am going to do. It's looking good man, keep us updated and show those pics :cheers:

There's no doubt about it, when I am all the way in the back of Tellico and it's getting late... the th400 will be the last thing I am worrying about. Actually my 4.3 has less than 10,000 miles on it, I picked it up myself new in the crate so I know what I have there. I tore the d300 down and it didn't need anything. I sealed it back up and siliconed the bolt head and threads and will put fresh gear oil in it after I swap the input. The 9" rear has 28 splines but by the time the truck is going I should have Moser 33 spline shafts or maybe 35 spline if they think I can run them... I'm letting them decide. I will have a d44 front, not exactly hardcore but not a crap axle either. All of this with 35/12.5 15's..and with my driving style (I crawl) it ain't gunna break 8)

I have killed 'em myself

I just weighed my th400 transmission is 135.6 lbs w/out TC and full of fluid TC is 35.4 lbs w/fluid

I will show you the right way to do it... if you survive the experience of opening up my donation package 8)

I have found some people that have studied this topic. The overall weight difference from a th350 and 400 is 10lbs. The rotating mass difference is also 10lbs. This guy claimed to have weighed both rotating components http://www.nastyz28.com/forum/showthread.php?t=58199 I also read where one guy seen no measurable difference at the dragstrip between a th350 and 400.

The biggest factors involved in me using the th400 is... 1. I already had it 2. In case I want to swap in a 350 engine 3. Bulletproofness with the 4.3 I'm easy on stuff anyways, a th350 would have easily held up. But I want to hear the numbers of power loss through a th350. I bet it's close to 20%, maybe 12-15%

I didnt explain the application either. It will be a rock toy, low range most of the time. 4.88 gears on 35" tires, the truck should be fairly light. If the transmission does lose 20% of power and the 4.3 makes 200 hp that would still leave me with 160hp. Probably more than plenty for what I need it for. How much does a th350 or 700r take? It doesn't matter either way, I'm still using a 400 :cheers: I think I have heard that going from a 350 to a 400 in the 1/4 mile will make you lose a tenth.

I think he meant to say track bar or maybe sway bar.

So I can sleep good at night knowing I will never have to worry about my tranny breaking

I was asked a few times how this can be done so here's how I am doing it... I have a 2wd 4" tailshaft th400 and a CJ7 long tailshaft Dana 300. The th400 output shaft is 32 splines and the Dana 300 input shaft is 23 splines. Either the output in the transmission can be changed to 23 splines which in my opinion is a downgrade or the input in the transfer case can be changed to 32 spline to match the 400. I got Advance Adapters to machine a 32 spline input shaft for me, it will take 15 minutes to install from start to finish. The outside diameter is the same, it's just the inner splines that are different from the stock shaft. The transfer case now has to be coupled to the rear of the transmission, if your tailshaft housing is round bolt pattern it will be a bolt-on maybe with some clocking issues but a clockring will fix that. Mine is a 2wd transmission so my tailshaft housing will have to be changed. JB Conversions builds 32 spline inputs for the Dana 300 also and Novak sells 23 spline output shaft for the th400. Novak claims their setup is stronger than 32 spline because the input shaft in the Dana 300 is female and enlarging the input leaves the outside thickness of the shaft thinner than they think it should be.

I have most of my parts collected for my MJ so I decided it is time to start the build thread. Specs will be... 89 MJ 4.3 w/quadrajet th400 D300 w/ Advance Adapters 32 spline input- twinstick. 4:1 possibly in the future 9" rear 4.88 Moser shafts 33-maybe 35 spline w/spool D44 4.88 gears on XJ leafs. haven't decided on the locker, maybe a lunchbox locker 35" tires chopped and dovetailed bed. tube and sheetmetal skins w/stock bedfloor