sm465 vs sm420 gear ratios (1 Viewer)

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TC regear = Orion - $1310 +

doubler = $1000 in adapters plus dshaft changes and the doubler case itself...few options there, price is similar

Personally, I'm a doubler fan, but the new Orion HD has potential...I'm personally NOT a fan of the current Orion, since it keeps some of the weaknesses of the stock case.
 
Cruiserdrew said:
We'll all sound like a bunch of echos here but:

The non-syncro first gear is a non-issue
The SM420 shifts fine and is strong as h*ll
The drive line mods are minor, but necessary (lengthen rear, shorten front drive shaft)
3rd and 4th ratios are a little too far apart on the SM420-not sure about the 465
Match the gear in your diffs to your tires-I run 4.56 and 35s, works well
60:1 or more crawl ratio is what you need for technically challenging trails
SM420 is a pretty simple swap but you need a 3 speed transfer case
I agree-rebuild the tranny prior to install in your Cruiser
The SM420 is noisier than the SM465 by just a bit

I did an SM420 swap a few days before CM04. (actually, I was grinding on the tranny reverse hump and put the front drive shaft back on the morning I left for CM04). Basically CM04 was my shakedown run for my SM420.....

I used one of Mike Smythe's plate adapters, and my 4 speed transfer case with a transition gear that Kurt with Cruiser Outfitters got for me. The 4 speed t-case is stronger than the 3 speed t-case. Slight gearing difference, however I don't think it's an issue.
I am running a 2F so I used a 3 speed bellhousing, and an index ring on the front bearing retainer. I also epoxied the TO bearing sleeve to the bearing retainer. I had to do NO drive shaft mods other than changind my '4 speed' slip yoke to a '3 speed' slip yoke, I had to make NO skid plate mods, and I had to do little custom fabrication.

I ran Poison Spider Mesa with the stock tranny at the CM04 pre-run and I ran PSM at CM04 with the SM420. NIGHT AND DAY difference on the trail. I am so sore at myself for not doing it sooner!

I originally used a junkyard SM420 that was shot. IT was jumping out of 3rd and 4th gear, and awas making some werid noises when I was driving down to CM04. I got a NEW Gamma Goat SM420 from a supplier in california. This tranny shifts just as smoothly as the stock 4 speed, and it isn't noisey at all.

Now for the things I don't like about the SM420.
1. I home brewed the transfer case shifter, and I have some problems with it clearing the tranny hump, so I disconnected the low range portion. It doesn't bother me that much so I really haven't bothered with it. The shift fork for the front drive engagement doesn't really work that well. AGain, this is partially due to my own design errors (originally I was going to do a twin stick, but I didn't have a good enough welder)

2. the gear spread from 3rd to 4th is a little too wide for the 2F with 4.11's in the diffs and 35'" tires. On the flats this isn't very noticable, but I do notice it going uphill. This is curable with 4.56's or 4.88's in the diffs.


Currently, I have a spare 4 speed t-case and a bucket with a 3 speed t-case gearset in it. I am debting rebuilding this case, and putting the 3 speed gearset in it. AT the same time, I plan on making a few t-case saver type devices and a stronger skid plate.

I am also debatign between going to 4.56 diff gears of 4.88 diff gears.

Anyhow, my 1/50th of a dollar.
HAve fun!
 
really quick question:

I'm about to install a 420 in the next couple weeks. I've read you need an 11" GM clutch disc, and I've also read you need a 10" clutch disc. Which one is correct?
 
10 and 13/16 = 11" if you are running an F 2F.....

12" if you are running a V8...

I have a 12" LUK clutch disc I bought from Orange. $30 (same price I paid) if anyone needs it.

I'll have a 465, Orion, Woody's adapter writeup done in a couple days. ;)
 
woody said:
TC regear = Orion - $1310 +

doubler = $1000 in adapters plus dshaft changes and the doubler case itself...few options there, price is similar

Personally, I'm a doubler fan, but the new Orion HD has potential...I'm personally NOT a fan of the current Orion, since it keeps some of the weaknesses of the stock case.

Does Marlin still make 3.64 gears?
 
"I've read you need an 11" GM clutch disc, and I've also read you need a 10" clutch disc. Which one is correct?"

from my experience, use the 11" if you have 3 speed flywheel. use 10" if you have the 4 speed flywheel. i pick up the 11" and assembled it with my 4 speed clutch parts and the disk was just big enought to be pinched between the flywheel and pressure plate. barely noticable 'till you start it and it drives off. luckily nothing was in front of me and in the 465's 1st gear it wasn't going very fast.
 
weird. i wonder if what i got was a 11-1/16". it barely pinched the disk. you mentioned 10-13/16"=11". i bet that was my problem.
 

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