th400 case lengths

7/30/2019 TH400 Case Lengths

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Case Lengths-


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1 Aluminum Powerglide 14 bolts

2 TH200 Metric 11 bolts

3 TH350 13 bolts

4 TH400 13 bolts

5 TH200-4R 16 bolts

6 TH700-R4, 4L60, 4L60E 16 bolts

7 4L80E 17 bolts


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Case Modifications-

The 2 "ears" on the case will need to be cut off with the weapon of your choice. Doing so will allow A LOT easier

installation. Be sure to not get any metal shavings inside the tranny.

The stock bellhousing is not removable. It can be cut off and replaced with an aftermarket one for safety standards

though. You can put an J.W. Performance Ultra-Bell Bellhousing on your TH400. The original bellhousing gets

machined off to install this one. It's SFI approved and yes, it is much stronger than stock

Weight-

4l80e- wet 255

4l60e- wet 175

TH400- wet 140

TH350- wet 130

Powerglide- wet 110

gear vendors overdrive- 40

Cooler lines-

TH350, TH250

Fitting Location Thread Size Flow Direction

Upper 1/8" Pipe Return/in

Lower 1/8" Pipe Cooler feed/out

TH400


Upper " Pipe Return/in

Lower " Pipe Cooler feed/out

4L60/4L60E/4L65E


Upper " Pipe Return/in

Lower " Pipe Cooler feed/out


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Stock lines will not bolt up to a th400. The use of fittings will be needed. Lots of different ways to do this. I put a

barbed fitting at each location in the tranny and then connected a hose to it. Then the other end connected to the

stock lines that I cut.

The use of an extra tranny cooler is recommended.

Governor / Vacuum modulator-

If you are not using a full manuel valve body then you will need to hook up your VM. Doing so is done by hooking it

to a vacuum source.

If you are using a FMVB, the use of the VM is not needed.

Driveshaft-

In most cases the stock driveshaft will need modified. You can buy an aftermarket DS from many vendors online. Or

just take you stock one to a local DS shop with the measurments and they will cut it for you. Driveshaft lengths will

vary from car to car depending on a couple factors. If the car is using a 12 bolt or a 9" you will see some variances.Also, if you are using different types of motor mounts compared to others (stock, solid, poly or motorplate). It is best

to measure the driveshaft for your application.

TH350 with a 9'' tailshaft will work with the stock DS

see Dennys drive shaft for info on measuring

Yoke-

-4l60e has 27 spline

-TH350 has 27 spline

-TH400 has both options, 27(long) and 32(short)

-T56 has 27 spline

PCM-

Can you drive the car after the swap, even though you haven't had the tranny items in the PCM turned off yet? Yes,

you will just have an SES light on that retains to all the A4 codes

I have a 6-speed tune in my car, is this ok with the th400? Yes, infact that is what most people flash the PCM to after

a th400 swap

External Links that might help-

Derty's guide

http://www.derty.org/photogallery/ca....php?cat_id=20

http://www.derty.org/ls1tech_trans_faq.htm

Transmission Dimensions- http://www.tciauto.com/Products/TechInfo/trans_dims.asp

What did a th400/th350 come in-

http://www.drivetrain.com/autotranscrossref.html


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Acronyms-

4L60E - actual part name for the Automatic 4-speed transmission

4L65E - medium duty 4-speed automatic transmission found in some trucks

4L80E - heavy duty 4-speed automatic transmission found in some trucks

700R4 - older generation 4-speed GM automatic transmission

A3 - 3-speed automatic transmission

A4 - 4-speed automatic transmission

ATF - Automatic Transmission Fluid

DS - Drive Shaft

FLP - Finish Line Performance (Vendor)

TC - Torque Converter

TFP - Transmission Fluid Pressure (switch/valve)

TH350 - Turbo Hydromatic 3-speed automatic transmission

TH400 - Heavy Duty Turbo Hydromatic 3-speed automatic transmission

VSS - Vehicle Speed Sensor

th400 case lengths

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