SM420 = last made in 1967, only year with reverse light switch was last one, 7:1 first gear, all 2wd or divorced t-case Adaptation to 73-older t-case = $150 or so with the SpaceGhost plate. (drivshafts extra)
SM465 = 1968 until early 80's, 6.5:1 first, 2wd and 4wd options and diff spline counts. Adaptation to 73-older t-case (plate adapter) = $450 or so. (driveshafts extra) AA makes a long adapter that works with all spline counts.
IMO, 465 is slightly more streetable, both are nice offroad. Both are heavy buggers. I went 465 since there was a better chance of parts due to newer, but not sure it matters.
SM420 is not that bad. They are cheap (paid $40), almost indestructable, and the adaptors are cheaper than the SM465. Plus the 420 is shorter than the 465. Is the 420 going to shift like a sports car??? Hell no. But I put it in for the 7 to 1 first gear. If I want smooth shifting I will drive my DD. The SM420 is probably the cheapest and realatively easiest way to get low gears. The converion cost me ~$400 total including driveshaft mods.
yeah, like rockwell t-cases make that comparison fair....lol
(I sit corrected again....getting used to this... )
I paid $40 for my SM465 and have another one on "reserve" for $50. Only issue is the conversion $$...plate is more, and you have to tap the output. I had no problems getting that done, but for whatever reason there are people across the country who can't find a machine shop that will do it....
thanks for the link correction....apparrently my coffee wore out yesterday afternoon...
i can only say my two rig's with 465's will pull better hwy speed's, and i don't think the 420 goes down the road as good and not much diffrence on the mountain either but for getting there and back i would rather have the 465's
i have had a 420 in my 45 and 40 and another 40 with a 465.
the 420 is old and hard to find parts or a tranny shop that wants to touch it.. not hard to work on.. but if your not into that than a rebuild will be a bitch..the 420 is a clunky shifting loud tranny.. and except for 3+ or 4 trails or moab maybe I never needed 1st with the transfer in low.. infact many times i used my ranger in od while using 1st because it was too low and i got too much slip..no momentum.. not to mention on the trail I really could have used a syncro to get into low ...
420 = old technology and crappy ride IMO
465 is better but still weighs a ton and clunky to drive..
cant say i was happy with either when i had them..
but then again.. i drive my 40 or 45 every day
heck when i sold my ranger/420 setup i made sure that the guy wasnt using it as a DD...
IMO, daily drivers outta be 4-speeds plus overdrive. Stock Cruiser 4-speeds rock on the road.
SM420 and SM465 both suffer from a "missing" gear... (pattern = G-1-2-3, with 3= to 1:1 ratio) Your in-town driving is all in 2 and the motor sounds like it's running too many r's...slip into 3 and it's running too slow for easy town driving.
NV4500 = G-1-2-3-OD and IMO is great on the highway but suffers a similar issue in town as the SM465/SM420.
The AA setup with the spud shaft is great for using the quieter 75+ transfer case and/or using the 2wd version SM465. However, it's ~5.5" length can be an issue...and your options for a double t-case are reduced.
IMO, a good daily/street/crawl combo would be the stock 4-speed tranny mated to a Marlin crawler box then to the stock t-case, or the RocBox doubler from AA.
I guess I'm just a little different....
I went SM420 because I don't mind my clunky boat anchor 3 spd a bit other than the too high first gear. Noise doesn't bother me, if it did I wouldn't drive a 40. My dream setup is a 420 with a ranger. Low low gearing, good highway, don't have to screw with my axle ratios. Much less expensive than the 465 because of the adapter. I also planned on rebuilding my 420 myself because there is no urgency to get it in, and I would like the experience. For a teenager on a budget, the 420 is perfect.
I guess what I'm trying to say here in the midst of all this 420 bashing, is that it does work for some people.
Advanced adapters makes an od unit with a 1:1 gear and an OD gear.. its like a tranny with only hi and low.. has its own shifter and goes between the engine and the tranny.. i only used it with a v8 due to drivetrain lengthe.. but with a ranger you can center the tranny stick in the original hole and still have lots of room behind the HEI on a v-8.. it worked good but it shifted a little funny.. heck that is a lot of gear spinning as you go down the road downside was that it whined even with full synthetic in it...
cruising GA.. you need to drive a EFI v-8 cruiser with a 700r and split case... t hat is damn quiet even without carpet...
The 420 and 465 splits are so close as to not really be arguable. Niether is optimal as a street tranmission with a 2F But parts for the 420 are still EASY to find unless you need a gear. Sticks Only, Novak, Standard Transmission and others will all supply you with rebuild kits for ~$150. I've rebuilt several 420's, and yeah, they shift slow, but they're not any noisier than anything else with big gears. Toyota makes a lower range 4 speed, the h41. 4.9 first gear, with the rest of the ratio's spaced out nicely around it. Great street tranny becasue fo that-it's not a granny low+ a three speed like the sm's. No adapters needed, no driveshafts to re-tube, and the ~5 to 1 first is ~40% imporvement of the stock yota 3.5 to one...mate it to an earlier yota transfer adds another 18% reduction.