Yes, the 65E is a factory strengthened 60E. Same basic story with the soon to be released 70E (in the Trailblazer SS which is supposed to have a Zexel Torsen gear type differential based AWD transfer case).

I'm not sure what the 65E is available in. You'll need to figure that out.

You'll also need to decide if it'll be stong enough for your application. If you're going to stay reasonable (450hp or less) a well built 60E should live with AWD. 65E should be good for a little bit more. I don't think that the 60E will live long (and prosper) with more power than that in an AWD application (my personal opinion here). There are a number of guys on the Truck board that have LSx series motors, AWD, and some form of power adder (Turbo, Super, or N20) and transmission troubles.

All the big transmission shops claim their 60E will live behind 700hp. But, most applications they put it into don't have 700hp worth of traction, which keeps them from having to warranty transmissions.

My guess: If you put a solid 600hp motor in front of a "built" (by some shmoe) 60E, and put the power to the pavement with 4 BFG Drag Radials or equivalent, I'd bet dollars to pesos it'll break the tranny.

Don't get me wrong, there are a few builders who seem to have figured out what it takes to do a 60E in an AWD application and have it live. Check out Rossler and FLT or is it FLP? (the guy building Parish's transmission) those two shops seem to know what they're doing.

'Dreamin'

 

hey man, thanks for the advice i appreciate it

 

Jimmy, I used the 4l60e from a 2000 t/a had it coverted to 4wd by the local trans shop( $192) used the universal adapter from advance adapters, it goes to a 4 bolt, then you use the sy ty adapter from the 700r4 to use the 4472 transfer case. the typhoon transfer case seems to be stronger than the sy,astro case the difference being the 32 spline output shaft, the tailshaft length is also different. if you order the adapter from anvace adapters,it has provisions for a reluctor ring,you don't need this, the speed sensor is on the trans case tailshaft. just get 2 brass plugs from anvance adapters, (there a odd size and I couldn't find them anywhere else),and plug the holes. In awd drive application using the 4472 transfer case only 30% of the power goes to the front wheels, that's only 300# tq if your putting out a 1000. That's the setup I'm using, but I'm only putting out 400 or so hp. On the transfer case i bought 3 cases, 1 typhoon , i bravada, 1 astrovan,(was looking for the 32 spline) had the 3 cases gone through by the trans shop, the bravada case needed a seal and bearing kit, the astrovan needed a seal kit and the small plastic scoop( I think it picks up oil for the mainshaft) had a damaged tailshaft housing so i replaced it. these cases were both 27 spline. the ty case was perfect,32 spline, put seals in anyway I hope to be running in the next few weeks If you decide to go this route, i'll look up the pt# for you on the adapter and the trans case adapter, there are 3 different adapters,the one you need is the sy ty one , I bought mine through GM parts,about $40. THANKS

 

The differences between Bravada, Astro / Safari, Typhoon, and Syclone cases are slight, but important. And sadly, it isn't a fixed thing based on model (ie not all Astro cases are XX spline) but is based on vehicle model and model year. I think early Bravada cases are 27 spline, whereas the later Bravada cases are 32 spline (if I remember correctly). As you noted, the Ty uses a 32 spline output. And the Sy case is different. Just wanted to make sure you were aware of the potential for differences.

There are a number of transfer case rebuilders' websites that detail spline count and fron flange diameter for the BW4472, based on model. If you are looking for a particular combination, you might first consult with one of those sites to know what vehicle(s) would be appropriate donors.

'Dreamin'

 

http://www.drivetrain.com/transferca...tml#Astroafari
...didnt list my 97 astro but im assuming its the lower slpine count anyways. WOuld you guys recomend keeping an eye out for a 32 spline just to be on the safe side?

Say I was to find a 32 spline t-case, what would it take to get it to work with the rest of my astro awd? If its alot of effort I might just go ahead and sell the astro and wait to find a cheap 32 spline bravada to come along. This will all end up on a completely custom chassis eventually but im just trying to reduce the amount of expensive one-off drivetrain stuff ill need, if it all comes from the same vehicle i wont be hunting down random bolts and all my measurements will be right there in front of me.

 

Quite honestly, I don't think the 27 spline vs 32 spline is really a big deal. The 27 spline stuff isn't quite as strong as the 32 but the margin is pretty small. Really the biggest deal is making everything work together, and if you've already got hardware, I wouldn't get rid of it just because of 27 spline rear output.

The 27 spline is used on the powerglide, TH350, 700R4 / 4L60E, and I think the 200R4, so its not exactly weak. You don't hear about drag cars with TH350's blowing up the driveshaft yokes. The 32 spline is a heavier duty unit, an is used on the TH400 and 4L80E.

Bottom line, whichever one you choose (27 or 32 spline rear output) you'll need to make sure that the rear driveshaft has the matching spline count. Any decent driveshaft shop should be able to help you out in this regard (changing yokes, whatever). And the front shaft will have to match the front flange diameter. Again, you should be able to make that work.

Now might be a good opportunity to invest in an aftermarket front propshaft (check out Gilbert) and a good set of driveshaft safety loops (break a u-joint or the propshaft at speed and you're likely need a new transfercase, tranny, engine, and maybe feet (and definitely a change of shorts)).

As noted previously, the Ty uses 32 spline rear output. For reference, the Syclone uses 27 spline. The net result: Its not a direct swap between the Sy & Ty transfer cases because the rear driveshaft slip yokes don't interchange. Gotta love GM always trying to keep us guessing.

'Dreamin'

 

Don't know if you noticed this or not, but they list the Syclone and Typhoon being available in model years other than 92 and 93. They are not. I wouldn't necessarily trust this website as Gospel.

The site I looked at was www.lightruck.com, and they listed 3 different models for the Astro / Safari. A '97 vintage unit should have 27 spline rear output and a 4.90" front flange mount (not sure if thats for the front propshaft or the front of the transfer case where it mounts to the tranny.)

'Dreamin'

 

cool ...i think ill keep the astro around then. Ill keep researching and collecting parts as they come along. Eventually get started on it thanks for the help everyone...keep the ideas coming

 

I've got the tcase out of a Typhoon in my garage if anyone wants it.. Its almost brand friggin' new. Don't mean for a hijack, just figurd I'd let ya know.

 

you giving it away or what?