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Re: [oletrucks] TH400 vs. 700R4 transmission

To: oletrucks@autox.team.net
Subject: Re: [oletrucks] TH400 vs. 700R4 transmission
From: Wayne Osborne <wayne@chevytrucks.org>
Date: Wed, 18 Jul 2001 18:19:15 -0400
Regarding the TH400----I used to have a chevelle 454 with it behind it, man
which i had that car back...  Oh well,
These are much heavier duty than the 350---I actually won a 50$ bet one
night as I told a guy i could put my automatic shifter is low gear, and
never touch the shifter and it would shift into second gear by itself. The
TH400 will do this---but you'd think the damn motor was gonna blow before
it did shift. Talk about a jerk when it did---man!!!!    Took his 50$ all
the way to the bank. DISCLAIMER---dont do this--if your motor is not
strongly built, it may not be healthy for the motor....
---wayne


At 07:42 AM 7/18/01 -0700, joe wrote:
>You kind of answered the question already by the statement "an awful lot of
>trucks using the 350/400 combo so it must be a good one".
>
>Like the 2-bolt / 4-bolt question, the 2 bolt was more of for the non
>working trucks that weren't going to need the extra low end protection due
>to added stress from towing or carrying heavy loads.  Most all work trucks
>have the 4-bolt main engines for that reason.
>
>The 400 transmission was also the heavier duty item between the two and that
>is again why you saw it in work trucks or behind Hp engines.
>
>I think I remember you saying the truck was mainly going to be used for
>cruising and so as long as you pick a 700R4 built after 1987 you should be
>just fine.  Your going to love the lower first gear ratio for acceleration
>and the overdrive for gas mileage.  I plan to purchase my 700R4 transmission
>from Bow Tie Overdrive http://www.700R4.com/ .  They got back to me with the
>following information:
>
>The Th-700R4 have the converter lock up which is a marvelous feature for
>eliminating the heat production inside the converter and increasing your
>fuel economy while lowering you cruise rpm a couple hundred rpm while locked
>up.
>
>Let me give you some numbers to play with.
>Th-700R4 (4L60) transmission with a heavy duty torque converter is $1020.00.
>We use nothing but late model (1988 to 1993) cores. We then perform a
>blueprint overhaul using only quality brand name components like Raybestos,
>Alto, Borg Warner, Torrington, Delco Remy etc. Every transmission features a
>new pump hardened steel pump rotor and vanes, hardened steel guide rings,
>double and stronger (high rpm operation) slider springs, H.D. Sprag, output
>Planetary with hardened ring gear and H.D. Pinion gears, New bushings
>(doubled in most major areas), Custom made (to our specs) one piece teflon
>seals, high temperature center seal, custom built servo assembly (our
>design), larger boost valves (both the main and the low/reverse), special
>accumulators (our design), custom shift calibration (our specification),
>nine frictions and steels in the 3/4 clutch pack with a special backing
>plate, special band anchoring just to name a few things. We perform over 40
>upgrades and modifications for increased durability and strength. The torque
>converter features a Kevlar friction, largest Lux dampening assembly
>available, torrington bearing to replace the thrust washer, largest
>available sprag, new steel pump drive bushing, brazed turbine vanes and the
>assembly is precision balanced for smooth operation. These converters are
>available in 1800 or 2200 stall speeds at the above price.
>T.V. (throttle valve) cable adapter system for your carburetor is $42.00.
>This cable controls all pressure manufacture and is the major outside
>influence on shift timing and feel. The importance of getting this system
>calibrated for your vehicle cannot be overstated. While other companies tell
>you it's important, we offer the parts and easy to follow instructions on
>how to establish this relationship correctly. All of our transmissions come
>with illustrated instructions on this critical set up.
>Zero to 300 PSI gauge with six foot hose and close 90 degree fitting is
>$28.00. This is a basic diagnostic tool that we require be installed during
>the start up and test driving to confirm the pressures are the same as when
>the transmission left our test stand.
>Speedometer calibration gear set is $44.00. This is all new Delco parts and
>is everything except the speedometer cable and the gauge. We will need your
>tire size and rear end ratio to accomplish this. When you get the
>transmission installed, all you will need to do is screw the speedometer
>cable onto the transmission drive gears and your speedometer should be
>correct! If you are planning to run electronic gauges, there is no charge.
>These transmissions already have electronic speed sensors built in that will
>interface with the after market gauges.
>Brake pedal switch that will disable the converter lock up whenever you
>press on the brakes. This feature will prevent you from killing the engine
>if you should skid the rear tires while braking. This switch will replace
>the old one under the dash.
>Plug in wiring harness for connecting from the transmission to the brake
>light disconnect switch or relay.
>
>
>
>-----Original Message-----
>From: Rick Carlisle <rcarlisle@home.com>
>To: oletrucks@autox.team.net <oletrucks@autox.team.net>
>Date: Wednesday, July 18, 2001 5:13 AM
>Subject: [oletrucks] TH400 vs. 700R4 transmission
>
>
>>Thanks for the responses on 2 bolt vs. 4 bolt engines.  Very helpful.
>>
>>I have another question.  I was virtually "sold" on using a 700R4
>transmission
>>before the 350 engine/400 transmission deal was offered to me.  I admit I
>>really don't understand the significance of one vs. the other except the
>700R4
>>has an overdrive that could help on the highway.  But I see an awful lot of
>>trucks using the 350/400 combo so it must be a good one.
>>
>>Can someone help me understand the advantages/disadvantages to using the
>TH400
>>vs. the 700R4?  Thanks.
>>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>
Wayne Osborne
1956 Chevy Pickup
LaGrange Ga.
http://www.chevytrucks.org
http://www.chevytrucks.org/wayne
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959

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