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Thanks, accepted, and back at ya.

I've dealt with a lot of different trannies myself and this is the first reference I've heard to 'case stretch'. Doesn't sound good. Maybe somebody needs to come up with a simple case girdle to addess that issue? That is unless it just gnarls out thrust surfaces instead of actually stretching the casting. I'm sure if the case is stretching on the thrust line there must be some deformation laterally as well, so it seems that metal fatigue of the casting is a rather scary issue to consider.

Sounds like the gear and shafts may be able to handle increased torque, but as Bob S said, it's well beyond ZF's design limits for applied torque in a high output installlation.
 

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A girdle for the ZF probably isn't worth the effort. The amount of actual stretch in the case isn't much. .002"-.003" over 30" or so of aluminum. ZF 5 speed guts are impressive. There's a bit more beef there than the NV4500, again, the lack of an iron case is probably the low torque rating reason.
 

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Automatic???

I may be opening a can of worms but why change the 46Rh to a NV4500 at all. I am in the middle of this type of swap in my 1988 wagoneer and I would think the auto would keep the 4BT in the power range by keeping the turbo spooled? I may be wrong but I have a 01' Dodge 2500 with a NV4500 in it and I have been beat by trucks that have autos many times. I even have the Banks Big Hoss Kit but they can always beat me at speed.

Any thoughts????:idea:
 

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I may be opening a can of worms but why change the 46Rh to a NV4500 at all. I am in the middle of this type of swap in my 1988 wagoneer and I would think the auto would keep the 4BT in the power range by keeping the turbo spooled? I may be wrong but I have a 01' Dodge 2500 with a NV4500 in it and I have been beat by trucks that have autos many times. I even have the Banks Big Hoss Kit but they can always beat me at speed.

Any thoughts????:idea:
I would want a lockup converter at the least, isn't the 46rh non-lockup?

i'm working on a 4l80e swap, personally :D
 

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46rh Is A Lock-up Transmission Non Electronic Vavle Body
not exactly...

i did a little research:

the 46rh came in lockup and non-lockup, the diesels came with the non-lockup 46RH. considered a 2 wire (non-lockup) and a 3 wire (lockup) as the way to tell the difference.

Unless he got creative, the non-lockup would be the easiest to put behind the 4bt because it mates up to the cummins/dodge flywheel housing.
 

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:nuke:
"Case Stretch" :eek: kinda makes you wish for those old cast iron cases like the NP435 & SM465
I AGREE! Does this thread seem like dejavu didnt we read similar stuff just a bit ago? Aluminum sucks unless you add Vanadium:grinpimp:
 

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interesting link
http://www.442.com/oldsfaq/oftrn.htm

8600 gvw for a 700r4 input torque 350 gearbox torque 650
15000 gvw for a 4l80e input torque 440 gearbox torque 885

i say it again. 650 for a used 4l80e, 800 for a controller and you have 1450 in a tranny.

or, buy a uses 700 for 600 and spend at LEAST 1000 "beefing it up.

remember the 4l80e torque converter bolts up to the GM stuff, unlike a 700r4.

best thing? say you are out in BFE, on vacation etc.... i think it would be easier to buy/swap a 4l80e, than to find another built 700r4.
 

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Averagef250 - I see you have an M5R2 behind a 4BT. How many miles have you put on it behind the 4B and any problems? I am in the process of building a 1990 F150 with a 4BT and in the interest of keeping the project moving I'm going to stick my M5R2 behind it and then rebuild a small block S5-42 I have at my leisure and then swap it in. The M5R2 has about 185,000 miles with no rebuild. The truck will be a pavement queen pretty much, no heavy off road. What is your experience with the M5? Sorry for the thread hijack.
 

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The M5R2 is a great tranny. I build several of them weekly and while that doesn't seam to say much for thier durability, every single M5R2 I've fixed has failed from horrible shifting practice, low ATF or running the wrong fluid, like gear oil. The early 89-91 trannies have weak reverse and 5th synchros which wear early even under easy use, but the later trannies are good. The M5's biggest weakness are the 3 rubber plugs at the rear of the top plate. Put metal ones in, don't shift it like a honda and change the fluid ever 15K and it'll last a good while. The M5R2 is a completely different design from the ZF. You'll never stretch the case of an M5R2. If you rediculously overload one you'll blow the teeth off the input and cluster.

The M5R2 is small, but it has 3 bearings supporting each mainshaft and countershaft. The gear ratios are the best you can get for a diesel. I think if you exceed the 350 lb/ft mark with this tranny under a big truck it won't last long, but otherwise it's a good choice for an economy built DD truck.

The M5R2 behind my 4BT has under 10K on it. I just changed the fluid out of curiosity (atf is cheap) and it looked great.
 
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