2004R VS 700R4 Differences




While both the 200-4R and the 700R4 came out at about the same time, there are quite a few differences between them.  The nice thing about them now is that while they both had their shortcomings when they were first released, they have been ironed out.  The only exception to this would be if you are looking at stock versions of these transmissions, which are becoming almost impossible to find.

In fact, they have been massaged so well that either transmission makes a great addition to a muscle car that still an old three speed GM automatic.  They both will bolt right up to any car that has a TH350 or TH400.  Real world fuel economy improvements are often as good as 30%.  Maybe even more important though is that your car won’t scream down the highway anymore.

 

700R4 VS 200-4R Similarities

These two transmissions are so similar, it’s almost a wonder that the factory produced them both.



TV Cable

They are both controlled by a TV Cable, which is a big upgrade from the old kickdown cable of old found on the TH350 and TH400.  This TV cable basically acts as a primitive throttle position sensor, which allows each of these transmissions to shift smoother and stay at the best rpm possible for peak performance and fuel economy.

The TV Cable is known to be a little finicky.  Is is one of the most common 700R4 problems.  If it’s even out of adjustment a little bit, it can cause the 700R4 or the 2004R to shift really hard, really early, or really late.

Overdrive

They both have overdrive gears, which is a first for GM automatic transmissions.  It was ground breaking at the time.  Todays modern 4L60E is a direct descendent of the 700R4.  This basic design and .70:1 overdrive gear are still present in it with minimum changes.  The 2004R is a bit more aggressive with a ratio of .67:1.

 

700R4 VS 200-4R Differences

 

 

Gearing

The overdrive gear in the 2004R is .67:1, which is a bit more aggressive of an overdrive than the 700R4.  This means that the rpm is even lower when driving down the highway with the 2004R.

Gear700R4/4L602004R
First3.062.74
Second1.621.57
Third1.001.00
Fourth0.70.67

 

As you can see, the gear ratios of the 200-4R are closer together than the 700R4, which makes it a better transmission for drag racing.

 

Telling Them Apart

The easiest way to tell any automatic GM transmission from the other is to use the pan bolt count and pattern.  It’s a bit more challenging with the 2004R vs 700R4, as they have the same pan bolt count, which is 16 bolts.

The best way to go about telling these two transmissions from one another is going to be to count the pan angles.  The 700R4 is almost a perfect 4 angled square.   On the other hand, the 2004R has 6 angles and looks more like the state of Nevada.  Please use the pic below to help you get a visual.

For way more on this the Identifying a 700R4 page has loads of information.

700R4 Transmission Identification

Here is the bolt count and pan pattern of most common GM auto transmissions.

Which one is right for you?

All things being equal, the 700R4 is a better choice.  It’s much more common and has better aftermarket support.  The gear ratios are closer together on the 2004R, which is a bit better for drag racing.  For street use, it’s the 700R4 all day long.

Conclusion

If you need a dependable transmission that will lower the RPM of your motor going down the highway, while at the same time increasing MPG, you can’t go wrong with the 700R4 or 2004R.  For most people the 700R4 just makes more sense, thanks to it’s broad aftermarket support and longer production life.


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