Which Case To Run With Th350 With Stock Axles (1 Viewer)

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i would not put a a 44 in there. thats about the same strength of the fj40 axle.

I was suggesting a 44 for cost and for a centered differential. I'd even suggest a 12 bolt or a 10 bolt - after all, they work fine in 1/2 pickups - but a 44, if you get a Scout one (or a JK one for that matter), is the same width as the '40. Also, the other reason behind the suggestion is exactly what you pointed out - it's the same strength as the one he hasn't broken.

What kind of mileage can you get with a 5.3 LS motor?

12 - 14 mpg. with a 6.0 you should get 14-16
 
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X2 on what Jim said. Dump the 454. Get sump'n more sensible, SBC. Unless your look'n to get into a project for lot's more $'s and rework'n the entire drive train just to run that boat anchor! You will never reap any benefit from running sump'n that large in a 40...
 
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X2 on what Jim said. Dump the 454. Get sump'n more sensible, SBC. Unless your look'n to get into a project for lot's more $'s and rework'n the entire drive train just to run that boat anchor! You will never reap any benefit from running sump'n that large in a 40...
easy to spend someone else's money and time... though, I must admit that's the first time I've heard a 454 referred to as a boat anchor.... especially compared to what came stock in the '40 (keep in mind, though, before you get all irritated at what I just said - I've referred to the GM straight 6 as a boat anchor as well... stupid low oil pressure beasts...)
 
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Wouldn't it make more sense to throw a beefier case and rear axle as opposed to an entirely different engine? Engine swaps are a little more difficult than an axle and case...
 
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easy to spend someone else's money and time... though, I must admit that's the first time I've heard a 454 referred to as a boat anchor.... especially compared to what came stock in the '40 (keep in mind, though, before you get all irritated at what I just said - I've referred to the GM straight 6 as a boat anchor as well... stupid low oil pressure beasts...)

:hmm: Was not aware of the new rule on MUD where we have to do a cost benefit analysis prior to rendering an opinion :hmm: AND no one was irritated, well at least then... At least when I drive my 40 and my 60 with their stock drive train I can wave to you all as I go by:flipoff2:
 
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Wouldn't it make more sense to throw a beefier case and rear axle as opposed to an entirely different engine? Engine swaps are a little more difficult than an axle and case...
the BBC and SBC are so interchangeable - I'm not sure that's true. The starter, distributor, carb, cooling system, even the exhaust from the exhaust flange back is the same (and is true with the 6.2/6.5 diesel)

:hmm: Was not aware of the new rule on MUD where we have to do a cost benefit analysis prior to rendering an opinion :hmm: AND no one was irritated, well at least then... At least when I drive my 40 and my 60 with their stock drive train I can wave to you all as I go by:flipoff2:

I think I saw you, I waved back from my Hummer :grinpimp:
 
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The mileage change doesn't really matter to me that much, it's not my daily driver. It's more less of a fun driver, the change in mpgs isn't enough to justify not fixing my current situation by swapping a case. I understand swapping any chevy motor is really easy, but it's just costs more than swapping a case plus axle(s). Then on top of that I really have no interest in redoing pretty much another harness, as I did mine in July, and I don't really want to run a computer.
 
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very good choice, the BBC weighs less than the straight 6 that was stock in there... and you have torque. I'm trying to find the balance in my '40 - it'd be so easy to make it weigh 6000 lbs, but I'd like to be in the 4500 lb neighborhood - and it will be close with my build - but we'll see in the end.
 
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Figured you guys would like an update, I think I'm putting a little too much power for a turbo 350. Kinda blew it up today while driving gently, metal shrapnel everywhere, maybe time for a bigger tranny...Everyone loves pictures:meh:
image-9.jpeg
image-10.jpeg
 
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no bracing on the transfer case? all the weight hanging off the back of the trans?... what is interesting is that is a 2 wd transmission with an adapter (not a very strong adapter, by the looks of it)....
 
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remember what I said about the shifter forks in the transfer case... this is what happens when it jams between hi and low. I bet your transmission, minus the adapter, is fine.... what you had was the transmission shaft spinning and the transfer case refusing to spin. Something had to give, and apparently the weakest link was that adapter - it allowed the transfer case to spin up.... pretty easy fix, IMO.... a couple laser cut adapter plates and an aluminum tube 7061 (not easy to weld, but very strong) or 6061
 
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Thats not the adapter that blew up, sorry for crappy cell phone pics but along the pan is cracked and falling off, pretty sure the adapter is fine...Thats all out of the side of the tranny...
 
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Also if this helps if you try to push it, you can roll it in park, reverse, neutral or drive and it makes a loud banging and jerks the cruiser. If I put the case in neutral between 4h and low it doesn't make any noise and rolls fine, thats what tells me the trannys done. Here's a slightly better picture my buddy got.
image-11.jpeg
 
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weird spot for it to blow.... that's all I know about that... normally the drum comes apart and then you have shiney, christmas-like tinsel all over the track... and bad words come from the track crew (not that I have any idea about this other than rumor... hehe)
 
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Your latest photo indicates a crack from non-supported span rather than torque twist. When a crack originates at a bolt hole (bolt pattern) running fore and aft that crack is normally from torque twist (too much torque). When a crack wraps around the circumference (like yours) that crack is normally from a long non-supported span. The rear propeller motor mount was designed to eliminate (or stabilize) torque twist, but it does not help a long non-supported span. TH400's were normally considered a poor choice for Chevotas because they are very much over-kill (which is ok), because they are so long that you end up with very little rear drive shaft length, and a longer non-supported span..
 
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It doesn't really wrap around, it's only on the side and there's cracks that run up the side of the tranny a little more. So would I need once I put a new tranny in it, a transmission cross member long with my transfer case cross member?
 

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