The 420 and Tcase come apparently come out of a 67 Chevy Longbox truck. I don't know anything about them but rockwell caught my eye. Are they any good? What are they worth in generally good shape? I got a guy wanting to sell both for $150.00 Worth it?
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Is a SM420 and Rockwell Tcase any good?
- Thread starter Gunny65
- Start date
euzoa
1/2 ton status
I dont know a thing about the rockwell, But i love the SM420 thats in my 65. if i remember right first is 7.01. but i do know they weren't designed for newer tcases
I was able to verify from him that yes, they did come out of 67 GMC pickup. It comes with the drive shafts, cross member, trans and tcase.
Is the Rockwell Tcase any stronger than say a 205 or 241?
Seems like $150 isn't bad. Anyone else know anything else about these two items?
Is the Rockwell Tcase any stronger than say a 205 or 241?
Seems like $150 isn't bad. Anyone else know anything else about these two items?
KansasTwister
1/2 ton status
like a 205 strength wise, but harder to find parts for i think.
The Rockwell 221 is similar in design to the 205 (all gears, similar size) but has a bunch of downfalls. Mainly, the only parts you can get for them are seals and gaskets. That may not sound like a big deal, but if the input gear doesn't match your trans or if you need/want to use a different u-joint than a 1967 truck needed, you're out of luck. With a 205 you have a stronger case with MANY options, many of which are still available brand new.
$150 certainly isn't expensive, but what can you do with driveshafts? And what if the input gear is chewed up? Or if any part of the trans or t-case isn't perfect?
The 465 and 205 are SO MUCH MORE COMMON that you can get any part you want for them relatively cheap, and they are the updated, improved versions of the 420 and Rockwell/NP200 cases etc.
So no, the Rockwell tag doesn't mean it's super awesome and 205's are so stupid overkill for just about any truck that anything more is again, overkill. There are trucks out there that need more, but you have to try REALLY hard to need more than a setup 205.
$150 certainly isn't expensive, but what can you do with driveshafts? And what if the input gear is chewed up? Or if any part of the trans or t-case isn't perfect?
The 465 and 205 are SO MUCH MORE COMMON that you can get any part you want for them relatively cheap, and they are the updated, improved versions of the 420 and Rockwell/NP200 cases etc.
So no, the Rockwell tag doesn't mean it's super awesome and 205's are so stupid overkill for just about any truck that anything more is again, overkill. There are trucks out there that need more, but you have to try REALLY hard to need more than a setup 205.
"Most" Rockwell T-cases were divorced versions,they had a drive shaft between the trans and T-case,so it can be used behind any tranny you wish,all you need to do is make a driveshaft to go in the tranny & a yoke to fit the T-case...I've seen only one rockwell that was not divorced,in a '68 K-20 we had come in at the junkyard..
I had a Rockwell in the Chevelle wagon in my avatar,I liked it,it sounded like a 6-71 blower due to the straighter cut gears...had a 454 powering it with a car TH350 ..it never gave any trouble the 7 years I beat the thing!..
The SM420 is a good tranny,lower first gear than any other GM one,and smaller than a SM465 overall,but still has PTO covers so a PTO can be used...good rock crawling tranny..I'd say for 150 bones its a deal--someone needing those parts to restore a 60's 4x4 would gladly pay a lot more,they are getting scarce,at least here anyway...the K-20 we had at the junkyard was cannibalized in less than 2 weeks,once word got out we had it!..
I had a Rockwell in the Chevelle wagon in my avatar,I liked it,it sounded like a 6-71 blower due to the straighter cut gears...had a 454 powering it with a car TH350 ..it never gave any trouble the 7 years I beat the thing!..
The SM420 is a good tranny,lower first gear than any other GM one,and smaller than a SM465 overall,but still has PTO covers so a PTO can be used...good rock crawling tranny..I'd say for 150 bones its a deal--someone needing those parts to restore a 60's 4x4 would gladly pay a lot more,they are getting scarce,at least here anyway...the K-20 we had at the junkyard was cannibalized in less than 2 weeks,once word got out we had it!..
I am going to take a look at the two pieces today. Check, input and output slop and a basic outside overview. If they look decent, I will get them.
Who knows, someday I may need them or someone may need them really bad. I know I could probably use them in about two years. That is when I may start a real crawler. It looks fun and I have the time and space now.
I did some looking around on the web and came up with basic kits. As stated, they contain gaskets, shims, and so forth. I didn't see any replacement parts at all except through other cases. Even so, $150 isn't bad if they are functional.
Thanks for the input. It is appreciated.
Who knows, someday I may need them or someone may need them really bad. I know I could probably use them in about two years. That is when I may start a real crawler. It looks fun and I have the time and space now.
I did some looking around on the web and came up with basic kits. As stated, they contain gaskets, shims, and so forth. I didn't see any replacement parts at all except through other cases. Even so, $150 isn't bad if they are functional.
Thanks for the input. It is appreciated.
