AA SM420 adapter

[66fj40x2]

I'm gearing up for the SM420 swap and ran across this AA adapter on eBay.

http://cgi.ebay.com/ebaymotors/ws/e...tem=7932100492&category=33733&sspagename=WDVW

Is it a good adapter or should I pony-up for a plate adapter from extreme bends or other mfgr? I sure like the price of the one up for auction but don't like the idea of a longer drivetrain and a shorter driveshaft. Any Input?

Mike

 

[Uncle Ben]

You answered your own questions! The AA adaptor is good quality but you have to remove your center crossmember (or relocate it). The plate adaptors work very well!

 

[66fj40x2]

I didn't even think about the cross member Plate adapter it is. It's worth the extra money not to have to jack with that!! Thanks Kevin!

 

[Outback]

If you want to go sm465 you could use Woody's adapter....

https://forum.ih8mud.com/showthread.php?t=20446

Check it out, maybe another idea.

Jody.

 

[66fj40x2]

Hey Jody, if I didn;t already have the 420 I might... Here's another question though;

Is there a special tool/puller to seperate the 3 speed tranny and transfer case. The last time I had Fat Boyz up here do it, but they have sort'a PI$$ED me off. They said they used a press and 4 ro 5 of their biggest boyz to get it seperated. I'll put a post on the Yahoo page too.

TTYL, Mike

 

[Uncle Ben]

Hey Jody, if I didn;t already have the 420 I might... Here's another question though;

Is there a special tool/puller to seperate the 3 speed tranny and transfer case. The last time I had Fat Boyz up here do it, but they have sort'a PI$$ED me off. They said they used a press and 4 ro 5 of their biggest boyz to get it seperated. I'll put a post on the Yahoo page too.

TTYL, Mike

If I did the whole plate adaptor chevy tranny again I would also go the 465 route. My 420 has served me well over the years but I did completely rebuild it before I first installed it years ago.

Pros about 420's
has low first gear
is shorter than 465
easily adaptible to J30 bell housing
Plenty of supply in salvage
J-30 shifter will fit



420 Cons
hard to find parts
noisey
T-case has to be clocked 5% for front drive
have to be stopped to put into 1st gear
can get stuck between gears (rare but can)
nearly same gear splits as J-30 in 2-4
fill plug on right side (covered by front drive)


Pro's about 465's
has low first gear
all gears are syncromesh
T-case doesn't have to be clocked 5degrees!
no shortage in salvage
new parts still in production
reverse light switch hole in every case
Fairly quiet


465 Cons
longer than 420
tougher to find 10 spline output
heavy!
front bearing retainer has to be machined



Thats a quick breakdown and I'm sure if I thought about it more I could double the lists. Bottom line is either tranny is a great upgrade in place of a 3 speed tranny! 465's are more modern and shift accordingly. One of the biggest advantages of the 465 is the fact the T-case doesn't have to be clocked so you don't lose 1.5" in clearance!

Sorry to rain on your 420 excitement just trying to possibly save you money in the long run when you get 465 envy and have to change things all over again.

Happy Cruising!

 

[Texican]

There are several of Spaceghost's adapters floating around, post a request up here in the wanted section, I bought one just last week for $100 never used........
They rock.
Butch

 

[66fj40x2]

There are several of Spaceghost's adapters floating around, post a request up here in the wanted section, I bought one just last week for $100 never used........
They rock.
Butch

Hey Butch, Thanks, I just posted it. Are these the type that clock the T-case, or require trimming the tranny? I think I'd prefer to trim the tranny for better break-over, but beggers can't be choosers!

Thanks, Mike

 

[Texican]

Hey Butch, Thanks, I just posted it. Are these the type that clock the T-case, or require trimming the tranny? I think I'd prefer to trim the tranny for better break-over, but beggers can't be choosers!

Thanks, Mike

These require a bit of grinding on the trans, not much if you can source the early driveshafts which you should have on a 66....
Butch

 

[66fj40x2]

Adapter Plates Located

With MUCH help from Butch and Nolen I have secured at least one and I'm pretty sure two (maybe three) SM420 adapter plates . Derrick Pennington will be getting one (not that he needs it with that new Ramsey 9500 winch ) and of course mine. While I have not met either man in person, I am very greatful for their help in securing these adapters. THANK YOU BOTH! I'm going to have to make wheel'n trip to Texas so I can buy dinner.

Mike

 

[Texican]

With MUCH help from Butch and Nolen securing these adapters. THANK YOU BOTH! I'm going to have to make wheel'n trip to Texas so I can buy dinner.Mike

We are both geruine A$$holes in person.......

Butch

 

[66fj40x2]

We are both geruine A$$holes in person.......

Butch

Sheit, with my line of work we outta get along great ... and I get paid to be that most days