The 420 trans will work fine. It's not much weaker than the 465 and a 6.2 goes nowhere close to the max power it can handle.
The 420 trans will work fine. It's not much weaker than the 465 and a 6.2 goes nowhere close to the max power it can handle.
05 2500HD CC LB LLY, 4x4, 3.73s 235/85R16's, webasto cab heater, to keep it warm.
03 Buick Rendezvous - When you average over 80 miles per day driving around, you need one of these.
85 K-5, 6.2, SM465, Rockwell T221, 1 tons, 36's. More goodies to be installed as time and money allows.
82 K20, 6.2, SM465, NP208, stock except for bed rack, snow plow, and glow plugs are on a toggle switch. It works great for plowing!
72 Postal Jeep - Yet another project
Awesome, thanks! I'm not planning a turbo (no point if I keep a 4 speed, if I go and swap out the tranny I may as well do the 4x4 conversion while while I'm at it. for now I just want a good clean running work truck for puttzing around and short cruises (we have a 55 mph speed limit on the highways here). I know people hook up 4bt diesels to the sm420 all the time so I figured since I'm not hot rodding it or anything it would be okay. I'll figure it out when I have the cash and parts accumulated. Thank you again!
Cool, I figured a N/A 6.2 wouldn't be a huge deal, long term I either was a short bed stepside that I'll put a good solid tranny in and a turbo diesel or I'll just keep upgrading this. I used to not want a long bed, but I've fallen in love with mine.
I was going to go with a 420 in my K-5 until we found out that the transmission in my buddy's yard was a 465, not a 420.
05 2500HD CC LB LLY, 4x4, 3.73s 235/85R16's, webasto cab heater, to keep it warm.
03 Buick Rendezvous - When you average over 80 miles per day driving around, you need one of these.
85 K-5, 6.2, SM465, Rockwell T221, 1 tons, 36's. More goodies to be installed as time and money allows.
82 K20, 6.2, SM465, NP208, stock except for bed rack, snow plow, and glow plugs are on a toggle switch. It works great for plowing!
72 Postal Jeep - Yet another project
I agree the 6.2 will not be a problem for the 420. I am planning on building 6.2 with all my parts for my 65 GMC 4x4 and it has a 420.
I did some investigating and found that the 6.2 and my 292 6cyl have almost the same HP and Torque rating.
I don't push my truck hard anyway so I am not at all worried about it. The 420 is also highly sought after in four wheeling circles because of how tough they are for their small size so that boosts my confidence even further for doing this.
This is irrelevant. HP is completely irrelevant. Torque @ RPM IS relevant. The 6.2L will shred the 420, eventually (seen it more than once). Quicker if used near capacity. Applying the same torque on a tranny at less than 2/3 the RPM will compound the applied torque exponentially. Even with the correct bell housing, I don't think you can fit a large enough clutch/PP, which is also a weak link when factoring torque/RPM. Also, the 420 is not dampened and will require a dual-mass flywheel, if it has any chance at survival, at all.
I don't know why you keep saying the 420 cannot handle the power.
I've seen 420's used behind high horsepower V8's and they've worked fine. I've seen them in medium to heavy duty farm equipment pulling 40 tons of potatoes for over 40 years with nothing but oil changes behind the old 5.0 V6 or even 454 V8's.
Dual mass flywheels? Really?
Man I guess we've been lucky all these years on the farms and other places I've seen them used.
If the 465 more modern? Yes, doesn't mean the 420 is crap. I still run the Rockwell T-221 T-case in my K-5. Is a NP205 better? Yes, but the Rockwell does everything I ask of it so it's not worth upgrading because a guy on a forum says so. If he has a 420 and all the shafts to make it work, run it until it quits. Then upgrade.
That's my opinion, for what it's worth.
05 2500HD CC LB LLY, 4x4, 3.73s 235/85R16's, webasto cab heater, to keep it warm.
03 Buick Rendezvous - When you average over 80 miles per day driving around, you need one of these.
85 K-5, 6.2, SM465, Rockwell T221, 1 tons, 36's. More goodies to be installed as time and money allows.
82 K20, 6.2, SM465, NP208, stock except for bed rack, snow plow, and glow plugs are on a toggle switch. It works great for plowing!
72 Postal Jeep - Yet another project