T18 DANA Transmissions

I have a 1973 CJ5 with a 360 V8.

I would like to know the spec on the T18 DANA and C18-15-24-5 Tranfer case. The driveshaft is only 18" long. I would like to replace the trany T18 with something else that would work with my setup and give me a 5th gear.

Thank you for you help

 

The t18 is is made by borg warner not dana, the transfercase is a dana and should be a dana 20 if stock. The transmission you have is far shorter than any 5 speed that would be suitable for a jeep. Really the only options you have is the nv3550 or the nv4500, both of these will shorten your driveshaft even further as they are both longer than your current t18 4 speed..

 

Do you feel like you need the 5speed? Or is it a want thing. Because you have one of the stongest 4speeds ever build(not the but up near the top) Let alone the fact you will loose another 4+inches of driveshaft by going to the 5speed.

 

Change your diff ratio's if you want better hwy economy.

 

What about adding an overdrive?

 

Not really possible with a Dana 20. A Dana 18 OTOH that would be the way to go

 

yep, and if its a T18A (6.32:1 first gear) you'll have no problem on take offs with less gearing

 

Wow a overdrive? what type, make or model? What does it take to install it?

Someone told me if I install the NV4500 I have to cut the jeep in half and add more space so the NV4500 will fit?

"wrote" AJ CJ5 Change your diff ratio's if you want better hwy economy

How can I find out what diff ratio's am running?

Thank you guys for all your help

 

Here is the calculator you need to decide on what gears you need in the diff's.


http://www.novak-adapt.com/knowledge/gearing.htm

You can find a close idea of what you have for gear ratio by jacking up a tire and rotating the hub one full turn and counting how many times the driveshaft turns.

for example if the drive shaft turned 4 times it would be 4 to 1 or 4.10's

If you want to be sure you need to take the diff. cover off and look on the ring gear you will see 2 numbers together such as 41 10. which again would mean 4.10's

 

There should be a tag on both axles that says the ratio. If there's no tag, look at the numbers on the ring gear and divide them: for example, 41 11 -> 41/11 = 3.73

Both the factory ratios - 3.73 and 4.27 - are fine on the highway. Does the noise bother you or are you thinking you might get better mileage with a 5-speed?