I can echo Lugnutz. A 1352-222 T5 replaced the SM420 in my 3600. The 57,000 mile original 216 with a 4.11 rear gear and a .72 OD does fine in 5th gear in fairly level country running 55. It's happy in flat land up to 70 or so. Now introduce Any headwind or hills and it's back to 4th gear. I've no problem with that. I do have a .83 overdrive T5 I've considered mounting up just to try it out. So far that hasn't happened. I should probably just let it go.
On 1'st gear the T5's 3.97 1st gear is also fine for normal driving or work. Now, that said I do sometimes miss the 7.02 gear in the original SM420 transmission. Places I miss the granny crawl gear, when loading hay in the hayfield, starting off with a loaded trailer or trying to creep along on a old rutted up two track road. But 90% of the time the T5 and its higher 1st is just fine.
RonR
Last edited by moparguy; 11/02/2021 11:08 AM.
