Upgrading Drivetrain

WV77CJ5

New member
Ok, right now i have a 258 I6 engine with the 3 speed transmission in my 77 CJ5. And I am curious if I can upgrade to a 4 speed and it will bolt in the same and what all that might change on the drivetrain or anywhere else. Also, if I go to the 4 speed will I later be able to drop a 304 in later on without too much of a change??
 

Get a T-18 4 speed that is a 4 with a Granny Low. Bolt right in but as for the 304 not really sure but think it will bolt right up as well. Othere s here will know more than I about this. tug
 
amc made it so that all of the motors would bolt right in. No need to find a different bell housing. Should have no problems
 
Thanks alot Tug, greatly appreciated. Now I just gotta call the guy that has 'em & see what he A$K$ for.... Thanks though
 

Ok, just talked to my dad and he thought that the guy said that the transmission was a T-4 four speed transmission and that the guy thought that I would have to change the bellhousing. Any ideas??
 
It's the same engine/transmission bolt patterns, if memory serves me right. The transfer case mounting pattern and output shaft are totally different, so you'll need to use the D300 transfer case that came factory behind the T-4. I wouldn't swap out a T-150 for a T-4. The T-4,T-5, and SR-4 4 speeds are light duty. They'll break if you look at them wrong. They all have better ratios than the 3 speed so swapping them in is tempting, but they won't hold up.

The granny-low T-18 is a heavy duty unit. I has great stamina and will make a Jeep much more capable in slow speed wheeling conditions. But in my opinion, it sucks for everything else. It works like a 3 speed in normal driving conditions, shifts like a schoolbus transmission and weighs a ton. I prefer the lighter duty T-176/D300 used in 80+ CJs for a simple swap. It is considered a "medium duty" unit like the T-150 that you have now, it's much stronger than the T4,T5, and SR4 but also much weaker than the T18.
 
By "break" what do you mean? Well see, the real reason why i'm doing the transmission upgrade is because I am having a slight grinding noise while I am just driving down the road, also because I am having a hard time downshifting to first gear. Along with that, unless I hold the clutch in for a few seconds then I can't shift into third without some grinding, and even after I hold the pedal down there is still a little grinding just less. This whole transmission was just rebuilt maybe 2 or 3 months ago and i have only put a little more than a thousand miles on it since then i believe. I think it is the synchronizers but I'm not really sure, i'm not a transmission guy. Any ideas?
 

If thats' the only reason you're swapping, rebuild the T-150. A shadetree mechanic shouldn't charge you much to rebuild that 3 speed, it's pretty simple. With a factory service manual you could do it yourself in a day or two. The T4 won't work with your T-case, and after you get that fixed you'll still have to shorten your rear driveshaft and get a longer front one. A T4 isn't worth that much trouble unless you can get the whole conversion for a REALLY good price.
 
well, the T-150 was JUST rebuilt. It was rebuilt in December I believe, so what would have made that happen that quick?
 
Abusive driving, poor quality rebuild/parts, letting it get low on fluid, getting water in the fluid..... If you speed shift or shock load it, then the T-150 isn't going to stand up either. It's a good transmission if you can live with the ratios, and there isn't any reason one wouldn't stand up to normal use. I got one sitting behind a built V8 and pushing 36s. That's alot to ask of it but it has held on so far, and it looks as if it will retire in one piece next month when I put in the T-176/D300.
 

what are you gonna do with your T-150 when you swap the other in?? All of the parts are from Quadratec and I went to check the fluid and it is suppose to only be up to the filling hole and when I took the plug out a good bit more than that ran out. But I know that I put the right amount in it when I filled it up after the rebuild. And honestly, i'm not that rough on the transmission, just muddin' is about the most abuse that it's taken and i'm the only one that drives it.
 
Engine Questions

Ok the T-4,T-5, and SR-4 all are horrible trannies likely just to cause you wishing you had gone to a stronger transmission. they can not properly take the wieght of Jeeps. sure there are prolly people out there who love them but as for me i dont. they are worthless. get a T18 if you plan on wheeling and using heavy and bigger mods. this is a heavy transmission that will not break down. as for all the rest you might as well not have a transmission. cause thats where your Jeep will be not running.
 
Ok, got the details on the transmission & transfer case w/ bellhousing and everything. It is a T-176 transmission with a Dana 300 transfer case,
I prefer the lighter duty T-176/D300 used in 80+ CJs for a simple swap. It is considered a "medium duty" unit like the T-150 that you have now, it's much stronger than the T4,T5, and SR4 but also much weaker than the T18.
Is all of this true? Because if it is then i'm definitely gonna put this in, will they all bolt up without any driveshaft changes or anything? The guy only wants $150 for all of this?? Isn't that a good deal for everything that i am getting and it's in good shape?
 

Dude, buy it! That is great deal. You'll need driveshaft mods, but it's worth it to get the T-176/D300 combo. You won't be loosing one bit of strength, and you will be getting much better gear ratios in both the transmission and the low-range in the Tcase. You'll need to shorten the rear shaft and either get a longer front or have your front shaft retubed.
 
How much does it cost to modify the driveshafts & stuff?? Also, I have availability to the driveshafts from the T-176 front and rear, they wouldn't fit in my CJ5 would they??
 
Did the T176 come out of a CJ5 or 7? If it came from a 5 then the shafts would obviously work in yours, so I'll assume it came from a CJ7. Get the front, it will work in yours without modification whether it came from a CJ5, 7, or 8. If they aren't going to throw in the rear for free, don't bother getting it. Just have your rear shaft shortened, the last one I had done was last year and it cost $40 at a local shop.
 

Alright, here is the total deal, i'm getting:
decent back seat w/ frame for $15,
T176 transmission & Dana 300 T-case & $150
Manual Steering Box good condition $25
BOTH driveshafts $25
Good Clutch - $10

What do y'all think????
 
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