700R4 Length vs TH350: What's the Difference?

Looking to swap out my transmission and can’t decide between the 700R4 and the TH350. I’ve done some research, but I could really use the community’s input on the lengths of these two transmissions and how they affect compatibility in various Chevrolet models. Here’s what I’m considering:

Dimensions Matter

  • 700R4 Length: This transmission measures approximately 30.5 inches from bellhousing to tailshaft.
  • TH350 Length: The TH350 is about 29.5 inches long.

Compatibility Insights

I’m mainly focusing on fitting one of these into a Chevy pickup. What should I be aware of regarding:

  • Crossmember Adjustments: Will I need to modify or relocate my crossmember?
  • Driveshaft Interchangeability: Can I use the existing driveshaft, or will I need a new one?

Installation Challenges

Are there any specific challenges you’ve faced when swapping from a TH350 to a 700R4? I understand the 700R4 has overdrive, which could be beneficial for highway cruising, but does that come with added complications during the swap?

Any personal experiences or tips would be greatly appreciated!

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The 700R4 measures about 30.5 inches in length, while the TH350 is slightly shorter at 27.5 inches. This can be crucial for tight installs!

Great point! Don’t forget about the width too. The 700R4 is wider, which might lead to clearance issues in some setups.

I’ve heard the mounting points are different between the two. Can anyone clarify how the TH350 mounts compared to the 700R4?

Yes, the TH350 typically has a fixed mount at the tailshaft, while the 700R4 usually has a crossmember mount. This can greatly affect swap compatibility.

Measurements aside, the shift patterns differ, which can affect how you drive. Have you thought about that?

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Good point, but my main concern is really the installation space! I just want to make sure everything fits before I start the project.

Both transmissions are robust, but the 700R4 can handle more power. Be cautious with your setup to avoid exceeding limits!

That’s true, I am aiming for around 400 hp. Do you think I should go for the 700R4 then?

Don’t forget about the drive shaft length! The differences in transmission lengths will affect this too, so plan accordingly.

Exactly! It’s easy to overlook the driveshaft, but that can be a deal-breaker if it doesn’t align.

I love how technical this conversation is getting! But seriously, if you’re swapping, just double-check everything.

Ha! Right? Who knew transmissions could be so lively? But on a serious note, your garage space will determine a lot.

Considering a swap is always exciting but also daunting! Taking measurements is a must to avoid surprises later on.

Truth! And remember, it helps to have some friends assist during installation—never hurts to have an extra set of hands!

Great topic! The 700R4 is commonly found in trucks, especially in the 80s models like Chevy C10s. The TH350 suits a lot of older muscle cars. There’s definitely some overlap, but it really depends on your project’s goals.

What about swap implications? Would the TH350 work well in an 80s Jeep YJ? I’m really considering upgrading my transmission.

The 700R4 has a lower first gear ratio, which can help performance off the line compared to the TH350. But fitting it in older cars might be a headache due to length differences and floor pan modifications.

A headache is putting it mildly! I tried swapping my TH350 for a 700R4, and the clearance was a nightmare! Definitely measure twice.

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The 700R4 allows for overdrive, which can improve highway fuel economy. If you plan to drive long distances, it’s worth considering over the TH350 for that reason.

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