Building a 1000HP rated TH400 transmission

Aaaaand we're back!
This time to assemble Kurt's 1000hp TTH400 trans with reverse pattern manual valvebody, for his Turbo Holden V8 project.
Following on from last episode's full gearbox disassembly and inspection - Corey, the beard of knowledge, is going to run us through the process of building a TH400 from the beginning, starting with a bare empty case. He's even kind enough to bestow apon us some small snippets of wisdom from his years of experience in the field. So be sure to keep an ear out for a couple of hot tips ;)
Massive thanks goes out to our boy Corey, the beard of knowledge, from Australind Automatics for all of his help. You can find them on facebook;
/ australindautomatics
1/18 Piggott Drive,
Australind, WA 6233
Check it out, and leave us a comment with your feedback.
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[@ED-fn7iz]

He put the forward drum backing plate on the direct drum. And vice versa the hub goes in the forward drum...this is so wrong....do not copy this video guys check your books...page 60 atsg online if you don't believe me...

[@lukechan5805]

Wow!! First thing i seen is what a unorganised workshop. still running the original thrust washer under output shaft no Bearing. didn’t watch much all of the video because of laughter read some of the comments below and new he didn’t know what he was doing. Cheers for the laugh.

[@Goodethanks]

Another banger boys! congrats on the 1k :D

[@STREETCARCULTURE]

Great vid mate!

[@jamieknight9636]

yeah fellas great vid thx. on thing if I install the 0.125 restrictor for the convertor feed will it affect my stall seed and lockup in the top end?

[@TorqHub]

G'day Jamie, I think that question would be best answered by your torque converter guy. He would know what parameters he built the converter to perform within. I doubt you'd see much change in efficiency but torque converters are a seriously deep topic that are rarely understood so it's best to ask your converter or trans guy their opinion. Thanks for watching mate.

[@desmondgriffin3924]

Do you know what valve body and clutch kit ?

[@leam1966]

cracky

[@jakestree1892]

Wheres the mods

[@lafinrat]

I didnt even watch the whole video and spotted MANY mistakes. He didnt check the reaction carrier end play, didnt check the rear unit and play before he proceeded to assemble the front unit, didnt load the rear unit before he set front end play, he put the forward clutch pressure plate in the direct drum and vice versa LOL LOL, he didnt measure ANY pump clearances, didnt check the rear band adjustment/servo stroke, used cast iron rings on a "1000 hp th400". This guy is no transmission "builder". Please change the title of this video to "How to ASSEMBLE a STOCK TH400, Improperly".

[@TorqHub]

Great feedback mate. I'm glad you've taken the time to share some knowledge with us. This video is not a tutorial. It was never meant to be, it isn't titled as such and we sure as shit aren't proclaiming that we know what we're doing. We simply document what we're doing. Corey did re do some stuff he had done because he had been distracted, the video editing of this was done poorly by us because we don't know what the hell we're looking at. Time will tell as to how well this trans was assembled. I'll be sure to post up in the "DIY Th400s for drag racing" fb group for any further info or criticism if we need it. Haha. Thanks dude.

[@inscoredbz]

I noticed that forward pressure plate and the forward hub was ass backwards. I was wondering if that was left like that and worked.

[@376LS3VY]

To the guys who noticed the mistakes , can you amagine what your machanics do without you knowing and them not telling you 🤷‍♂️ , this bloke fixed the mistakes . And we all know its hard to concertrate and not be distracted when you habe a camera videoing you and asking you 200 questions whilst your trying to do something. Get off ya high horse keyboard worriors

[@Iatolaazzahola]

I sh^t when I saw all of those same blunders. lol He says; I still look at my assembly manual. FWIW, I couldn't work either with that guy talking to me. I could barely stomach the part that I did watch with that stupid tribal jungle beat going in the background. This whole thing is a WTF!

[@GOLDY91SS]

Good luck with the trans, I have personally been fucked over by Corey at Australind Automatics. From being straight up lied to, to over charged and abused as a customer. As a mechanic myself this kind of experience made me realise why people think mechanics are just out to rip people off! Just my 2 cents worth.

[@roycefriesen7632]

Why dont you pre soak the clutch plates?

[@Albert-nb9dm]

Made to impress , not very helpful.

[@Chopperdog]

That's just a stock th400.

[@lknight4461]

At 6.05 you have put the forward hub in the wrong way!!!!

[@TorqHub]

Mate, that's an excellent pick up! You've got a keen eye for detail. It seems that having your mate film you and ask stupid annoying questions while you're trying to work can be somewhat distracting. It was picked up sorted out during that clip and then edited out. The length of the video was already getting too long so it was decided that would get the cut. Thanks for watching L Knight!

[@mattrodgers4878]

I noticed that as well.

[@Anarchy-Is-Liberty]

OK, so you're telling us what some of the parts are called/named, but you're not telling us where you got them, what they are made of, what company makes them, etc. Please don't tell me your are using standard used TH400 parts for a 1000HP+ motor, right?

[@TorqHub]

Hey mate, This transmission was sold to me as a 1000bhp capable package and we have labelled it as such. It was then torn down and inspected/reassembled as you've seen in our videos. Time will certainly tell as to how well this holds up but we are confident that its fit for purpose behind a basic turbo Holden v8 engine. Thanks for watching Anarchist.

[@Anarchy-Is-Liberty]

@@TorqHub OK cool, but it would still be nice to know what company built this thing. Was it TCI, ATI, B&M, other? Thanks.

[@TorqHub]

No its not from any of those guys, i bought it in unused condition from a friend who originally had it built by trans shop in South Australia. Corey at Australind Automatics is the guy in these videos stripping and checking/ reassembling this one. Corey also built the 1200hp rated hd case th400 for the procharged ford windsor combo in the xy falcon on the recent channel videos.

[@andrewhunter6371]

That is about as stock as stock gets.. Where do you come up with 1000hp and NO TSI 4045 and NO 34 element sprag? I can go on and on about failure parts.....

[@TorqHub]

Any insight into potential failure points that you have to point out would be welcomed and taken on board for when we step up this trans combo for the built engine. Atm it will only need to handle 550-600 bhp Max. This trans was sold to me as a unit built to withstand 1000hp. That's the only reason the video is titled as such. Both the th400 videos we have done are just checking what I've purchased. It wasn't a fresh build with parts we had chosen. Going off my memory I thought it had both the case saver and 34 element sprag inside, along with some 4l80 bit and better clutches etc. I cbf checking back through the footage to check honestly. We done a poor job of editing this one as some of the procedure was done again differently and edited out by mistake. We will see how this trans holds up soon enough as the project with be commencing here soon.

[@carlospsdz155]

Put in the clutches DRY?

[@cre8tivegarage157]

Super dope! Awesome job! Never need a transmission being put together.

[@waltercox804]

Dry clutches is for video content only

[@johnnybrigham8154]

Hi Corey we’re did you get the 3/8 T handle from also I need the pump alinment clamp Please Help nice job on the 400. Ps your height gauge is from Who??? Thanks Corey.

[@twomontess]

How long did it last without him soaking the clutches in trans fluid ?

[@megaramathor]

i was wondering the same thing, ive always been told to soak em for a while before installing em

[@timothysirmon1655]

Soaking is just for setting clearances some trans builders believe it’s a more accurate way to set them

[@mattrodgers4878]

As long as you let it run for long enough to let fluid soak into the frictions before hammering on it, the clutches will live just fine. It’s much cleaner and easier to set clearances and assemble when dry. Start it up, run it thru the gears, make sure it’s full, by the time you get it on the ground the fluid has soaked into the frictions.

[@twomontess]

@@mattrodgers4878 great to know. I was always told to soak the clutches

[@TorqHub]

@@mattrodgers4878

[@1BENT8]

The end result of that rebuild is no drive gears........ needs the forward drum assembly to be put together properly............

[@ohcamsrazor1966]

Great work Australind Automatics 👍

[@jonalarcon8564]

When you cut that bell off just take it to the tip and give it a good toss !!!!!

[@robmotown1]

Well......... when I built my first th350 with upgrades I.e extra steels and clutches, trans bake valve body and mods to case, clearance for every clutch pack to manufacturers/ performance spec, machining all parts to accept new and more parts, and machining for Torrington bearings in all places to replace bushes, It was a lot more complicated than what is shown here!!!!! But still not complicated for a person that is mechanically minded and can use a lathe with confidence!

[@TorqHub]

Sounds like you've built yourself a killer th350 Robmotown1! This transmission had already been built, modified and upgraded beforehand, this was basically just a 2 part video consisting of strip down, check over and reassemble to confirm everything was OK. Thanks for watching

[@jonalarcon8564]

Good job mate , but you should cut that bell off and install a super bell by JW , that way you don't need a shield or transmission blanket, just had one built by Chino hills transmission rated over 1000 horses

[@TorqHub]

Good call, we've actually just done a build using a JW adapter bellhousing to put a TH400 behind a Procharged SBF. Great product 👌🏻

[@hankclingingsmith8707]

WHERE IS YOR CASR SAVER ?? IT RECOMMENDED ABOVE 600HP. THERE ARE MORE MODS TO HOLD 1000 HP.

[@TorqHub]

The trans does have a case saver.. thanks for watching Hank.

[@Daves-hereagain]

Question What would be a good replacement trans to replace a 4L60e? The 4L60e has a 3-4 shift problem It is just like the trans is put in neutral when shifting from 2-3. The engine is a ATK 290 hp 5.7

[@TorqHub]

Gday DW! Whilst we aren't experts in this field, we do know that you can have the 4l60e rebuilt with upgraded components to handle more than 290 hp no problems at all. They are a great box for low to moderate hp applications when built right. Doing a transmission conversion to a more robust unit for your hp level would certainly be cost prohibitive we would assume. Go and speak to a reputable trans shop in your area and I'm sure they'd be able to sort your lacklustre transmission performance out easily enough. Thanks for watching mate

[@swampmilitiaoutdoorsinc9276]

A th400 is easily adapted to a ls it'll bolt up to the engine it requires a flexplate spacer and drilling the holes out in the flexplate to bolt to the 400 converter the th400 isn't computer controlled like the 4l and 6l80e so it's a popular swap for ls swaps and what I'll be going with

[@johnnybrigham8154]

Dura prem gasket part# for 400 and from who? Thank you Corey??

[@TorqHub]

Not sure if Corey will see this comment mate, might pay to get in touch with him via the Australind Automatics FB page or call the shop 👌🏻

[@ericperry4934]

What hard parts is suggested for a 1100 hp / 1000 ftlbs 8000 rpm th400 build . With a auto/manual valve body PRND123.

[@TorqHub]

Consult your local trans builder for a solid recommendation, but I'd suggest you'd want to be looking at 300M shaft/drum combo, 34 element sprag, quality raybestos clutches and rollerised output shaft bearing at a minimum.

[@ericperry4934]

@@TorqHub does the drum needs to be aluminium or oem

[@TorqHub]

Sorry, I should have been clearer. OEM drum does work well in most applications. 300M input shaft, drum shaft, output shaft. We have those in the TH400 we put in the Procharged XY falcon in our most recent video. We did give a full description of that trans in Ep1 of the series.

[@hammatime94]

Speed round or what?

[@stevecurtis5321]

Great job guys

[@TorqHub]

Thanks Steve!

[@keysautorepair6038]

No way that will hold 1000 hp maybe 500 before you break the bell housing.

[@mk1cortinatony395]

Never seen an auto built with dry plates!

[@inscoredbz]

I've seen it a lot. Never seen any problems either. They always let it idle in neutral for a few minutes, then went through the gears on the lift. I'm like you tho, I soak mine. Stupid not to.