Tranny Swap

[Roger]

Since some of you forgot more about Jeeps than I knew in the first place, I'm going to guess someone can answer this question for me:

Can a T-4 Transmission by removed and a T-5 installed without any modifications or adapters?

I have a T-4 and I'm thinking of Installing a T-5 for better hwy running. Any thoughts or info??

Jeep: "Just Empty Every Pocket"

[DEADMEAT]

i have a T5 in my 80 cj7. to be honest i dont really use 5th gear that much on the hwy, except for longer drives. i can take some measurements of my T5 to compair to you T4. i would think if they are the same length, and the same bolt pattern, it would work out.

[Roger]

i have a T5 in my 80 cj7. to be honest i dont really use 5th gear that much on the hwy, except for longer drives. i can take some measurements of my T5 to compair to you T4. i would think if they are the same length, and the same bolt pattern, it would work out.

Thanks for the reply Deadmeat, I've done a lot of research and it looks like they are the same size. I was wondering why you don't use 5th gear - is it because you can't go fast enough on the 91 or the 15 due to the heavy traffic? We rarely have heavy traffic on Hwy 18 ;^)

[DEADMEAT]

i avoid the 91 like the plague. unfortunatley i have to use some hwy, the 15 just isnt that bad.
I dont use my 5th gear that much cause it only really works once you get up to 65 or 70, and even there, you dont really have much power. if you are doing a lot of hwy driving, i would say it has worked out pretty well for me. i cruise at 75mph @ about 1500-1700rpms ...once i get away from the IE.

[Roger]

i avoid the 91 like the plague. unfortunatley i have to use some hwy, the 15 just isnt that bad.
I dont use my 5th gear that much cause it only really works once you get up to 65 or 70, and even there, you dont really have much power. if you are doing a lot of hwy driving, i would say it has worked out pretty well for me. i cruise at 75mph @ about 1500-1700rpms ...once i get away from the IE.

You know I was giving you a bad time in fun right?? Heavy traffic out my way is slamming on my brakes because a covey of quail are crossing Hwy 18.......

I appreciate your offer to take measurements, but you don't have to crawl under your Jeep to do that. I found a website that gives all the specs for T4's & T5's. According to the measurements, number of splines, etc, it should be a perfect swap. I was hoping someone who's actually done the swap would chime in with some info.

[SAR Jeeper]

I have the T5. The T4 to T5 is a common swap, very easy bolt in. Probably one of the best place for CJ info would be CJOFFROAD.com.

I use 5th gear often enough. I'm running 3.73 gears with 35" tires. I go into 5th gear at around 60-65. I don't have a tach, just shift by ear and feel. My 5th gear is noisy, but it's nice to have that overdrive.

[Roger]

I have the T5. The T4 to T5 is a common swap, very easy bolt in. Probably one of the best place for CJ info would be CJOFFROAD.com.

I use 5th gear often enough. I'm running 3.73 gears with 35" tires. I go into 5th gear at around 60-65. I don't have a tach, just shift by ear and feel. My 5th gear is noisy, but it's nice to have that overdrive.

Hey thanks for the information.

BTW, Since you have the name SAR, I was wondering if you are involved with Search & Rescue?

[SAR Jeeper]

yes. I'm a SAR TECH II and based out of the Los Angeles Police Dept. I'm urban, but my heart is with wilderness, but my career says otherwise.

[Roger]

Well, but the picture of your Jeep It's pretty obivous you enjoy your time off out in the wilderness!!

Go LAPD! You guys have my respect!

[DEADMEAT]

You know I was giving you a bad time in fun right?? Heavy traffic out my way is slamming on my brakes because a covey of quail are crossing Hwy 18.......

I appreciate your offer to take measurements, but you don't have to crawl under your Jeep to do that. I found a website that gives all the specs for T4's & T5's. According to the measurements, number of splines, etc, it should be a perfect swap. I was hoping someone who's actually done the swap would chime in with some info.

ya i know its all just fun and games we'll have more fun out on the trails between the muddin and the :beer:

[DEADMEAT]

I have the T5. The T4 to T5 is a common swap, very easy bolt in. Probably one of the best place for CJ info would be CJOFFROAD.com.

I use 5th gear often enough. I'm running 3.73 gears with 35" tires. I go into 5th gear at around 60-65. I don't have a tach, just shift by ear and feel. My 5th gear is noisy, but it's nice to have that overdrive.

hey SAR Jeeper, how does your jeep do off road with the 35s and the 3.73 gears. do you still have the power with the big tires.

[SAR Jeeper]

hey SAR Jeeper, how does your jeep do off road with the 35s and the 3.73 gears. do you still have the power with the big tires.

It's not TOO bad offroad, but sucks on the highway. I will be regearing soon, probably to 4.56's. The biggest change is my MPG. I went from 18 highway with 32" AT's to 13 with the 35" MT's.

[Roger]

It's not TOO bad offroad, but sucks on the highway. I will be regearing soon, probably to 4.56's. The biggest change is my MPG. I went from 18 highway with 32" AT's to 13 with the 35" MT's.

Deadmeat,

Could the change in gas mileage be because your odometer wouldn't be recording the same because of the bigger tire diameter? Just a thought.

[SAR Jeeper]

I checked my mileage and speed via GPS that I mount on my dash. I told my insurance company I would only be driving about 500 miles a year, so I disconnect my speedo after I reach those 500 miles.

[Mitch]

Steve,

Who say's Jeepers aren't smart?