TH400 The real answer

[yullose]

Mine just went in last week and fit better than I could dream of.
The minor issues were:

1) Factory trans mount will work, but holes need to be slotted wider.

2) Shifter cable bracket needs to be relocated

3) Factory shifter needs to be changed over to accept reverse 1-2-3 shift pattern. Two bolts will remove the factory detent plate. I cut a piece of metal to fit inside the original detents, welded it in, ground flat and re-cut new detents.

4) Driveshaft needs to be replaced. Using a short tailshaft TH400, mine measured 53-1/2" from the trans seal to the rear U-joint C/L.
Not wanting to risk using/shortening the OEM shaft, I opted to have a brand new shaft made with 1350 solid U-joints. The rear joint will be a conversion joint from the 1350 shaft to the factory Buick yoke.

 

[charliep]

Thanks for the photo's very helpfull. From what I'm reading is a fairly easy swap. We have an ATI flexplate so no problem there. Just ordered a reverse patten plate for the B&M prostick. We already had an aftermarket double hump crossmember. I need to get a new u-joint to swap over the 400 yoke. Anything else I'm missing?????

I was able to fabricate a bracket for the shift linkage on the 2004r that allowed me to still use the neutral safety switch and backup lights that are still in the column. I wonder if the TH400 shift linkage comes out in the same spot.

Ohhh where does the speedometer cable plug in??

 

[yullose]

Thanks for the photo's very helpfull. From what I'm reading is a fairly easy swap. We have an ATI flexplate so no problem there. Just ordered a reverse patten plate for the B&M prostick. We already had an aftermarket double hump crossmember. I need to get a new u-joint to swap over the 400 yoke. Anything else I'm missing?????

The driveshaft length is different. I don't think you can use the same shaft, it would need to be shortened or replaced.
The conversion U-joint I mentioned was for the new driveshaft I'm making.
I'm having one made that takes bigger 1350 U-joints, and needed to convert the rear joint to fit the factory pinion yoke on the rear diff. Eventually I'll get a bigger aftermarket pinion yoke to fit the 1350 joints.
I just figured if I was going to make a driveshaft, I may as well make it strong as possible right off the bat.

I was able to fabricate a bracket for the shift linkage on the 2004r that allowed me to still use the neutral safety switch and backup lights that are still in the column. I wonder if the TH400 shift linkage comes out in the same spot.
Ohhh where does the speedometer cable plug in??

I think it's close enough to use the factory stuff... (I removed all that stuff off my car.)
I also don't have a speedo hookup on my trans... The big freeze plug near the back of the trans is where it would normally go.


Also... I forgot to mention you will need a new dipstick and tube.
I ordered one from Summit Racing... It was around $30-$35.
It must be specific to the B.O.P bellhousing though...

 

[charliep]

I've been told that the 2004r driveshaft will work with the TH400

 

[yullose]

I've been told that the 2004r driveshaft will work with the TH400

Then all the better...
I don't trust them myself, and didn't even measure or try mine.

I was standing right alongside a Turbo Buick on a chassis dyno when a factory shaft came out from under the car on the top end of a pull...(130mph)
The U-joint bearing caps smacked my boots...

 

[charliep]

I hear that. My application is an Olds but the driveshaft and joints are small.

 

[yullose]

The dipstick and tube you need is PT# ATI-406491 from Summit Racing.
$35.95 + S&H.

 

[Ttype6]

I daily drive mine and it has tons of torque down low. Granted, I have billet whoo-daddys and hardened this and thats

Send it off to one of the reputable vendors of this forum for a built 200 with the good stuff in it.

Having billet parts does nothing to prevent clutches from burnig. This guy isn't complaining about hard parts breaking. He's complaining about direct clutches burning. He's already got the godd stuff in it. It was simply put together by the wrong guy. The reason your clutches aren't burning is because the guy who built it used the right clearence in the direct clutch pack,and the right servo return spring. This is how you get the timing right in a 2-3 upshift. By the way,that clunk so many hear during a 3-2 coast down is evidence that your third gear timing is off. The reason his clutches are burning is because the guy who built his tranny didn't correct the third gear timing. He chooses to ignore the fact that he's not burning up the band. Is the material on the band more durable than the material on the direct clutches. No,the clutches are being abused because of the incorrect timing. No clutch on earth can withstand this abuse for very long in any transmission. This problem is easily fixed. A 2004r with incorrect third gear timing won't last long behind a 100 hp motor for very long. So he'e going to ignore this and assume I'm making all this up and get rid of over drive and the TCC lockup. BRILLIANT!!! There is a good side to this story,however. With that low powered motor he's running,he'll never have to deal with transmission problems again. You can't help everybody. When would you sleep?

 

[norbs]

This is what you need, just get out the visa card

4l80e 1200 hp rated

 

[charliep]

If that 4l80e isn't built right I tear that up too. I'm so tired of these companies making high HP claims it makes me sick. Like Ttype6 said to the best of my knowledge I have not hurt any hard parts yet. In fact in all my years of racing the only hard part I ever broke was a input shaft on my C4 in my Stang. I currently run a SBF in a dragster and have hundreds of passes on a glide without problems. These 2004r trans are hurting clutches. I really don't care how they are going it only matters if I have to remove the POS every 5 or 6 months to rebuild. My goal it to have a transmission that last's for a few years of crusing around and a few trips to the track each year. If I'm asking too much let me have it. I have given this builder 3 tries at it and a previous builder 2 tries at it. After 3-4 thousand dollars I'm taking the easy way out TH400 done!!!!!

 

[DonnieShort]

I'm going to say this with my fingers crossed as not to jinx myself but.........

I dyno'd out at 606.6hp on a VERY burnt up 2004r, clutches were absolutly smoked as Russ can attest. Went through my tranny myself ( first one ever ) with Russ' help with parts and set up, no billitt anything ( except for a super servo )just a hardened Art Carr drum, blues in the directs, alto red's in the forwards and 4th gear and this thing shifts like mad. I have never felt any tranmission shift as good as this one does. It also feels like I picked up some hp in the process. This car will has run 125+ mph in the quarter on Nitto's with the fuel pressure reg. vac line off ( opps ) in which the mph could have been in the 128-130 range had it had more than 40psi of fuel.

I said all of that to say this, my car is very capable of putting down 625hp and well over 700 ft/lbs of torque to the rear wheels and this tranny has done great. I have not done any T-brake launches with it, yet however my point is with the power and low end torque I'm making there is no reason why a 200 couldn't live behind a low 13 sec car. If you want a 200 that will live give Russ Merritt a call and he can get you fixed right up.

 

[Ttype6]

My goal it to have a transmission that last's for a few years of crusing around and a few trips to the track each year.

If you put a 400 in your car you'll probably never have to do it again.There one of the toughest transmissions out there.

 

[charliep]

The deal is done. I pick the TH400 up Saturday morning. Will be driving around that night!!!!

 

[yullose]

The deal is done. I pick the TH400 up Saturday morning. Will be driving around that night!!!!

Take it for a ride up near the Pottstown area... I hope to have mine finished and out on the town that night too.
McDonalds on High St. gets pretty packed with heavy hitters on Saturday nights...

Maybe even a little side-by-side action after the traffic clears later in the night.

 

[charliep]

yullose, you ever get on del val racing or goracig? Haven't been to Pottstown in quite a while. I'm originally from Plymouth Meeting/Norristown area.

 

[yullose]

I don't get on godragracing much anymore, and only get on the delval once in awhile...
I use the same name on those sites too...

A buddy of mine was down your way last weekend and cleaned a few clocks with his Gray T-type...
He's from the Pottstown area too...

As long as the weather is nice, there's something going on...

 

[raflyer]

What about a Turbo400 with a gearvendors set-up??? Best of ALL worlds!!!

Let's see, killer/super strong tranny (400), overdrive that handles 1200+HP and nice tight gear spread that a turbo motor loves. That would be 5 shifts in the 1/4!!

I'm thinking of going this route,

3K total price = Durability, drivabilty, gas mileage :biggrin:

 

[norbs]

What about a Turbo400 with a gearvendors set-up??? Best of ALL worlds!!!

Let's see, killer/super strong tranny (400), overdrive that handles 1200+HP and nice tight gear spread that a turbo motor loves. That would be 5 shifts in the 1/4!!

I'm thinking of going this route,

3K total price = Durability, drivabilty, gas mileage :biggrin:

Well you got the idea, but theres more to add. You also could go switch pitch converter and have 2 stall speeds, from 2000-5000 if required. So when you go into overdrive the converter stops slipping away......

 

[raflyer]

Well you got the idea, but theres more to add. You also could go switch pitch converter and have 2 stall speeds, from 2000-5000 if required. So when you go into overdrive the converter stops slipping away......

Which 400's had the switch pitch or lock-up option?

 

[49-blues]

Yullose- in the first pic- what is the electronic thing with TS on it a modulator?