Synthetic transmission oil

[frankr]

I'm about to rebuild the 46RH transmission in my 34 Dodge.
The hemi motor has lots of power and torque.
I know the 46RH are not the best but, I make a lot of long trips and really need the overdrive.
I will probably get a high HP level 3 viper rebuild kit from PACT transmissions
and install a big transmission cooler.

Which fluid should I get:[S
1. PACT's "green" synthetic trans fluid they call Raptor Blood?
2. Royal Purple's synthetic fluid
3. Regular non-synthetic?
Anything better?
Additives?

I really want the transmission to last and I can't help it...I have a bad habbit of beating up the power train.

Thanks RRR
Frankr
1934 Dodge 392 Hemi[ddd

 

[old man dave]

I never use synthetic lubricants because they seep out of every gasket and make your transmission or differential look bad.IMO

 

[Screamin' Metal]

IF your gonna rebuild your trans, and all, yes, run your synth. fluid in it. Heat doesn't break it down like the regular fluids. Also, get the trans cooler that has the cooling fan on it.....the enemy of a auto-trans is heat!
A big stout motor in a heavy car puts alot of heat in your fluid. Also, while your plumbing up your cooler line, put on a spin-on filter block also, that extra surface area and line will have a extra cooling effect. The added filter also mean more cooling, and you'll be able to keep your fluid clean without dropping your trans pan all the time.....saving wear and tear on your pans bolts. (I normally stud everything anyway....I hate stripped bolt holes!)
Also, Have a B&M drainplug brazed into your trans pan.....
[