91' 2.3L AOD to T5 Swap Rear End Gear?

[Gone Blue]

This is likely a dumb question, lol. I have a really nice 91' LX 2.3L AOD car that I am going to swap a T5 into. Just picked up a complete 87' 2.3L T5 car for $300 to use for the swap. My question is what rear end gear should I run? My AOD car has a 3.73 and the T5 car should have a 3.45. I am thinking I should keep the 3.73 gear but didnt know if there were any down sides to running the 3.73 gear with a T5 other than fuel economy?

 

[evintho]

Firstly, your auto trans is an A4LD. AOD's came behind V8's. Secondly, why not just swap the rear gear from the '87 T5 car to the '91? Ford spent millions in R&D to determine the proper gear ratio for each car. They usually got it right.

 

[Gone Blue]

Firstly, your auto trans is an A4LD. AOD's came behind V8's. Secondly, why not just swap the rear gear from the '87 T5 car to the '91? Ford spent millions in R&D to determine the proper gear ratio for each car. They usually got it right.

Cool, thanks for the clarification on the transmission. I certainly can swap out my current 3.73 for the 3.45 out of the T5 car. I plan to pull the 3.45 gear to have, whether I use it or not, before I scrap the car. Was just wondering what other people have done on a T5 swap like this. Other than fuel economy, are there any other concerns with running the 3.73 gear with a T5? To your point, I am sure that Ford picked the 3.45 for the best all around use of the car. This car is weekend toy for drives in the county and thought the 3.73 would give it a little extra pep?

 

[Shawneebear93]

It would give it some more pep off the line but the engine would turn a higher rpm on the highway. How much higher? Not sure, have never done this myself.
@Asha'man did this maybe 20 years ago but I haven't seen him post in some time. Good Lord, I've gotten so old.

 

[Gone Blue]

It would give it some more pep off the line but the engine would turn a higher rpm on the highway. How much higher? Not sure, have never done this myself.
@Asha'man did this maybe 20 years ago but I haven't seen him post in some time. Good Lord, I've gotten so old.

Thanks Shawneebear93. That is what I was thinking too. I was looking to see what other people have done with an auto to T5 swap on a 2.3L car. I cant be the only one doing this I would think? Unless if someone has, it was 20 years ago, lol

 

[Clb1047]

I did this swap over 10 years ago. Definitely worth it. I have a’94 8.8 rear with 4:11gears. ( maybe 4:10, I forget). My car’93 convertible turns over approximately 3100 rpm at 70 mph. I average 20 mpg pretty much no matter how I drive.

 

[Clb1047]

Some info about my car. 93 convertible. 2.3l 185000 miles. Runs great. The only thing left stock is the engine and paint

 

[Gone Blue]

Some info about my car. 93 convertible. 2.3l 185000 miles. Runs great. The only thing left stock is the engine and paint

Clb1047, awesome, thanks for your reply. I thought the stock auto 3.73 gear seemed like it should be a great fit with the T5, just wanted to make sure the motor would pull that gear OK, the torque monster the 2.3L is, lol I assume you installed a standard 2.3L T5 and not one from a SVO ? Thx

 

[Clb1047]

Clb1047, awesome, thanks for your reply. I thought the stock auto 3.73 gear seemed like it should be a great fit with the T5, just wanted to make sure the motor would pull that gear OK, the torque monster the 2.3L is, lol I assume you installed a standard 2.3L T5 and not one from a SVO ? Thx

Standard t-5. I bought an entire junk car,92 hatch, just for the tranny. You will need a different drive shaft. I found out that the 4cyl auto is the one with the unique one. All other applications are the same. I added a hurst comp shifter and a svo clutch and flywheel. Good luck with your swap. Probably the best upgrade I’ve done next to chassis stiffeners. Gary

 

[Gone Blue]

Standard t-5. I bought an entire junk car,92 hatch, just for the tranny. You will need a different drive shaft. I found out that the 4cyl auto is the one with the unique one. All other applications are the same. I added a hurst comp shifter and a svo clutch and flywheel. Good luck with your swap. Probably the best upgrade I’ve done next to chassis stiffeners. Gary

Ok cool, Clb1047! I bought a 87' hatch for my parts car and did keep the drive shaft as I wasn't sure if I could use my auto one? Thanks Gary, I appreciate all your info. Brett