Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Hello Guest, we are proud to now have our Wiki online that is completely compiled and written by our members. Feel free to browse our Jeep-CJ Wiki or click on any orange keyword when looking at posts in the forum.
Looking for recommendations on what to replace the weak T-5Transmission with? I like the idea of an Overdrive but rarely use it so its not an absolute requirement. Suggestions on what would be a worthwhile upgrade that would still play nice with my Dana 300 and otherwise factory drivetrain.
I'm no Transmission expert but according to Novak................
"These transmissions [T-4 & T-5 ]are popularly replaced with the SM420 and SM465 transmissions, since they share a similar bellhousing bolt pattern and compact installations."
While both are very good Transmission , the sm 465 has a larger than stock input bearing housing which will require machining the bellhousing. The main shafts on both will have to be replaced to mate to the Dana 300 . Better choices if you wish to remain stock are the T-176 or T-18 . Either way driveshafts lengths will change.
84 CJ7 4 banger-owned since new in 1984 bought off truck at dealership - rebuilding 258, T176 with Sniper EFI D300 4:1 Lomax gears Twin Sticked 1 piece axels with locker
84 CJ7 4 banger-owned since new in 1984 bought off truck at dealership - rebuilding 258, T176 with Sniper EFI D300 4:1 Lomax gears Twin Sticked 1 piece axels with locker
Looks like a 6 speed is out of the question due to overall length. A NV4500 is possible but probably is cost prohibitive. I guess looking for a 420 or T-18 should be a priority.
I swapped my CJ7T-5 for an AX15 using a Novak adapter, fabricated new Transfer Case twin sticks, lengthened the front shaft, shortened the rear 3", fab Transmission mount, did the flywheel at the same time, throw out bearing is a pain as the length was off so I used Novak's adjustible construcktifukation and it's seems to be holding up well.
I needed a highway gear though.
On road daily driver with the odd trail.
That would definitely be the easiest swap. I know the T 176 will mate up to the Dana 300 easily. The T 176 is considered a medium duty Transmission and is used in Jeeps with a V8.
By looking at the OP's profile I thought he was already running a T 176??
That would definitely be the easiest swap. I know the T 176 will mate up to the Dana 300 easily. The T 176 is considered a medium duty Transmission and is used in Jeeps with a V8.
By looking at the OP's profile I thought he was already running a T 176??
I wanted a full synchro'd Transmission so waited until I found a 5-1 first gear T-19 (6-1 are out there, but harder to find) T-18 /19's with Transfer Case adapter are the same length as a T-5 , so no fussing with Transmission mount or driveshafts. A T-176 is a bolt in swap too, as mentioned
You can’t go wrong with any of these medium duty transmissions: AX15, NV3550, or NSG370. All have Overdrive gear with fairly low first gear. Perfect for CJ7 ’s.
I swapped from a T-5 to a NV3550 from a 2001 TJ. NV3550 is an upgraded version of the AX15. Both good transmissions behind a four or six cylinder and the closest match to a T-5 in size and gearing
Minor complications:
NV3550 input shaft uses a pilot bearing whereas the T-5 used a bronze pilot bushing with a smaller I.D. I found a pilot bushing the right size and it works fine, but on my next rebuild I intend to have the crank machined for the correct pilot bearing.
If not already done, will have to convert clutch linkage from mechanical to hydraulic.
Bolts right up to engine with CJ clutch and diaphragm.
Dana 300Transfer Case bolts up but tailshaft flange will have to be drilled for correct clocking, or use an adapter. I choose to use an adapter for two reasons; better engagement of splines, and I was worried about weakening the tailshaft flange drilling so many holes.
Factory skid plate positions the Transmission angle close to correct, I just drilled new Transmission mount holes.
NV3550 sits back several inches further than the T-5 . I had to cut out a few inches from the bellhousing pan and fab up new shift boots.
Factory Transfer Case lever is tight to put back on, but it will work. You'll need to grind a small part of the Transmission case gusset. (sorry to all you twin-stickers, I simply like the factory look).
As noted both driveshaft lengths will have to be changed and angles checked.
Lastly, after it was all done I used an acetylene torch to bend the shift lever to a comfortable angle.
