904 OH tools needed

what do I need or fab for tools to overhaul a 904. other than slide hammering the pump out & the right type pliers for the big ring for the ext housing, what do I need for the clutch packs & anything else? thank you for your time.

Don't need a slide hammer at all.

The rest is basic tool, even c clamps to compress the clutch spring.

A chain with a screw pulls the pump out.

I actually used a really long 3/8 bolt with a large impact socket(36mm for my jeep hubs) as a makeshift slide hammer and it pulled the pump real easy.

You can make a slide hammer for the pump with some 3/8 threaded rod, a couple nuts and a 1/2" drive deep socket. I have a universal front clutch compressor I've used for years. I'll see if I can find a link for it.

Here is the tool. I bought this because I was doing a lot of different transmissions at the time and this has never failed to work for me.

compressor tool

This also looks useable and it's cheap.

cheap tool

I think I have a slide hammer & I will try the C clamps & if no go I will go ahead & get the cheap(er) of the two eBay item, thanks guys!

Here's cheap compressor. Made it in 10 min. Piece of exhaust pipe that fits the spring retainer with a window for the snap ring pliers, 2 plates & a piece of allthread. All from scrap metal I had laying around.

Smaller (lb/in & lb/ft) torque wrenches, slide hammer (3/8" NC), pump alignment tool (big hose clamp), clutch spring compressor, asst. snap ring pliers and picks, feeler gauges & dial caliper, dial indicator, "shoe horn" tool to get the pistons in, tools to compress the servo springs are handy.

If you have a steering wheel/harmonic puller kit take a couple bolts about 2" long and attach it to the yoke with some nuts.
Then use it and a vise to compress the clutch drum spring

Works well if you don't have a tool that's the right size.

You guys are good! I'm ready to get on it.

I never used the pump alignment tool. I just put the loosely assembled pump into the empty trans case backwards without the o ring, started a bolt to keep it from rotating in the case then torqued the pump bolts.

^^^ also noted.

Don't need a single bolt or chain to get the pump out.

Stand it on the bellhousing, tap tailshaft. Usually falls right out.

Watch the how to rebuild a 727 video, it's in that too.

I'll watch it

That might work, if the tailhousing was off of it, but everything in front of the output shaft would come along with it. And hit the floor if someone wasn't able to catch it. Sounds a little "rural" to me.

If the 904 pump housing is like a 727 just use a short chain and pry bar. I just use the two threaded holes in the housing to bolt the chain, then run a bar through the chain resting the end on the bell housing face. Give the bar a sharp pull and the pump housing will pop right out. Pretty simple, "rural", maybe but it's easy and fast.

In a pinch this works if you first adjust the front band tight.
That holds the front clutch retainer and everything behind it.

Only thing that will come out then is the pump. And of course any fluid if you don’t drain the trans.

Tighten front band, find an old screwdriver, slide between band and case, against pump, tap it out. A vice and deep sockets works for the clutch spring. Valve spring compressor works on front servo cover. Snap ring pliers and a feeler gauge for clutch seal install is all you need. Guy that showed me how to rebuild the first time tapped on pump splines with a dead blow hammer while pulling on pump, slid right out. I did more tranny work with no tools than I do now that I have all the right tools. Simple trans to work on.

that's good stuff. I'm feeling alot better about this.

I'm suppose I'm guilty of having more tools around here, that have only been used once or twice, than I should. And I've made stuff that duplicates the function of expensive tools. Either way - engine, trans, rear, chassis, whatever - having the right tools makes a big difference. If I have to find a good used tool for the cost to make sense, I will. So much of this stuff can be had cheap on ebay and other places. Transmissions are one of those thing things - you never do just one, then never do another in life.

Or maybe a couple of longer bolts in three spots in your pump to catch it... Maybe put some towels down for when it falls out. It will "fall" on the floor the distance from the TC input the edge of bell. Put a wood block under it too. So many solutions.

All it has to do is drop about 1/2". Not dropping it off the empire state building.

Done at least 100 just letting them drop out while standing on the bell, never broke anything yet!

Yeah, I LOVE hillbilly engineering. Saves me money all the time when working on things. All good, even Rural works a lot of times and takes less time. Efficient!

Too many tools, guilty here too but must add one last hack. One time at the track we pulled the front pump by tapping it with a screwdriver, and did the front clutch retainer by one guy pushing it down with 2 hammer handles, and the other doing the snap ring.

the tools i have made over my lifetime for one time use is staggering !
when i got monroe's 727 book, i made all the tools necessary for one of those transmissions that i didn't have already, and then, have not used them one time !
got into front drive transaxles. had to fab up several tools for them.

just figures i guess. but i have lots of specialty tools.

Much appreciated guys! I think I can do this now & I will watch the vids. what clearance should I shoot for in the front & rear clutch packs & I am assuming you check em dry? & there was something I saw about discs being grooved or flat & one type is better for one or both of the clutch packs (iirc).

I always check the clearance after the discs have soaked in ATF for half an hour.

I prefer grooved/checkered in the front and smooth in the rear.

John that would make sense that they would expand a bit from that. Noted & I will go with the clearances Cope mentioned.

Don't forget to check the bushings. You can find reasonable bushing driver sets on ebay. Check out What It Takes Transmission's web site for a good schematic. They also sell oddball parts for decent prices. Here are my 904 build specs:

73 904 complete
4.2 billet front band lever (Cope Racing)
Cope Racing heavy duty band strut 
Cope Racing rear billet servo
New sprag inner race, springs and rollers
Cope Racing Front semi-rigid band red lining
Cope Racing Low reverse band red lining
Teflon pump support rings
Unrestricted pump support oil feed
Blocked front pump vent and relocated vent to upper tail shaft
Drilled front clutch retainer for quick piston release
Blocked accumulator - .002" clearance between piston and valve body
Front clutch:  5 - .061" Alto Red frictions, 5 - .068" Kolene steels.  Clearance = .060"
Rear clutch: 4 -.061" Alto Red frictions, 5 - .068" Kolene steels.  Clearance = .036"
Cope Racing 4 pin Low gear front planetary 2.74 first gear, 1.54 second gear (factory steel 4 planetary from Cope Racing).  Replaced thrust washer
Replaced all bushings
Used original rear planetary thrust washer
Replaced front clutch return spring with Cope Racing multi-spring clutch retainer
Total end play .013"
Gear train end play .009"
Front band adjustment - tighten to 70 inch pounds, back off 2 turns
Rear band adjustment - tighten to 70 inch pounds, back off 2 turns
Output shaft support bolts - 150 inch pounds
Pump body bolt torque - 160 inch lbs
Front servo pivot rod plug - 150 inch lbs
Tail housing bolts - 24 foot lbs
Pump to case bolts - 175 inch lbs
CSR transmission shield
ATI transmission pan - bolts 150 inch lbs
A&A Trans Brake - bolts 70 inch lbs (per A&A)
Air tested front, rear clutches, front and rear servos using 30psi.

Good luck with your build.

Thanks bro, I gotta get my printer hooked up! EDIT some of those tricky mods you posted, is there a vid or a book on em? MORE EDIT no shift kit (or did I miss it)? race only app?

Good thread guys, I had my 904 built last year by Mopar Billy's brother. It works great but its almost totally stock other than the front springs and a valvebody. I have a low gear 904 and an A-1 trans brake vb I want to build on my own. So far I have successfully taken it apart haha.

Humpty, were you able to move the vent back far enough to clear the CSI shield? On mine it looked like the shield covered the area where the rear vent would be. Thanks

You're halfway there!

He he. Sorry for the brain dump. Check out Carl Munroe's book: https://www.amazon.com/Torqueflite-727-Transmission-Handbook-HP1399/dp/1557883998

Also check out the tech section on Cope Racing's website.

This setup is for a street driven manual valve body. It's been 6.30 @110mph and seen more than 250 passes.

Here's where I put mine. No issues to date:

6.30 pass at Cordova last October:

https://m.youtube.com/watch?v=YSNmSkJh_XE