[heyjude076]

We are running a TH400 behind a mild 396BBC with 3.73 rear gear in a 39 Willys. I would like to reduce our highway cruising RPMs and was contemplating different rear gears. It was suggested that a 200R4 (with overdrive) would accomplish the same thing and is a direct replacement for the TH400.

Will the 200R4 bolt right up to the block and transmission crossmember?

[454C10]

I recommend that you keep the th400 and add a gear vender OD. 200r4 are expensive and are a pain to setup. 200 governors and TV cables are a huge hassle. And unlike the th400, the 200r4 never seem to shift when you want them to.

[joe_padavano]

I'm going to disagree on this. The 200-4R in stock form is a hand grenade, but the Turbo Buick community has found and fixed all the weak points in this trans. Gear ratios are much better. Most 200-4Rs come with the unisex case, so it will bolt up to a Chevy (some early cases are BOP-only). I've never had a problem with shift points. Seems that most of the problems are due to an improperly adjusted throttle valve cable.

The 200-4R uses the same crossmember location as the TH400, however the trans is physically shorter so you will need a longer driveshaft. It also uses the smaller TH350 front yoke. There are several trans shops that specialize in the 200-4R. Definitely use one that caters to the Turbo Buick crowd. There are a number of well known mandatory upgrades, including the hardened stator support, the intermediate drum with billet shaft, and roller thrust bearings. You can choose lockup or non-lockup converter.

The Gear Vendors OD unit is a good piece, but you'll spend more going that route than getting a well-built 200-4R. It's also considerably longer.

[SSedan64]

Here's a few 200-4R builders with good Reputations that are close to you. >>
Extreme Automatics http://www.extremeautomatics.com/tra...ons/2004r.html
Lonnie Diers
Cincinnatti , Ohio
(Quickt) on TurboBuick.com

Vince Janis
Janis Transmissions - Web site under construction.
1507 Kenmore Blvd
Akron, Ohio 44314
(JanisTrans) on TurboBuick.com
1-330-753-6609

With your 3.73 rear gear, a (CQ, CZ or KZ) coded 2004R trans would have the best shift calibration. These came in the Late 84-88 SS-MonteCarlo w/305 Eng. & Factory 3.73 gear. The Olds H/O-442's (KZ) coded trans will work, w/307 Eng & 3.73 Gear.
Or a ValveBody & Governor from a CQ,CZ or KZ trans swapped into any 2004R trans. As stated above 2004R's do need a few Mods to be reliable, so do most other trans.

[heyjude076]

Originally Posted by SSedan64

Here's a few 200-4R builders with good Reputations that are close to you. >>
Extreme Automatics http://www.extremeautomatics.com/tra...ons/2004r.html
Lonnie Diers
Cincinnatti , Ohio
(Quickt) on TurboBuick.com

Vince Janis
Janis Transmissions - Web site under construction.
1507 Kenmore Blvd
Akron, Ohio 44314
(JanisTrans) on TurboBuick.com
1-330-753-6609

Thanks for the tips. These people are in my "backyard" and plan to talk to them. If you know of anything good or bad let me know.

http://www.rosslertrans.com/index.htm

Thanks

[Cousin_Joe]

I put a 2004R behind a 383 SBC, and it sucked. Found out it was just a generic unit from a V6 Monte. Swapped in the VB and governor from an SS, and I was impressed with the diffrence. I always thought I had cable issues with the shifting, but the VB made quite the improvement. I know the 400 is heavy duty, but my opinion of the 2004R went up after I upgraded.