[Beau Diddly]

I have a '94 FZJ80, and plan to swap my 4BD2T (still attached to the manual tranny). I need the overdrive, so I have no use for the stock Isuzu manual tranny, but I'll use the bellhousing. My goals for this project are longevity, more power to tow (9K lbs, albeit very rare occasions), and finally increased MPGs for cross country hunting trips. I would like it to be comfortable enough for my wife to enjoy trips in it, but it won't be a DD. I decided to go with a manual because of the increased efficiency and easier/cheaper maintenance, so the NV4500 seemed to be the best choice.

I had planned to use Diesel Tim's adapter, but my challenge is, at the time, no one made an adapter from a NV4500 to my stock T-case (HF2AV). Others have gone to a FJ60 split case, then change out the axle, but the extra work and loosing my ABS doesn't sound appealing. Allmaras recently started making an $800 adapter for the NV4500 to the HF2A T-case, so he's the only game in town. Should I go this route, I'm aware of Dustin's history and the risk. My only hesitation is the NV4500 isn't easy to find and certainly not cheap, then add all of the adapters.

My question: I haven't really consider other options, so I'm not dead set on any of it, including manual vs auto tranny. Are there other feasible options I'm missing? I've read many references to Longbow's configured A440 tranny, though I have quite figured out exactly what this procedure is. Any other suggestions?

 

[astr]

Longbow's approach should also work for your A442F tranny which, in my opinion, is a better tranny than the A440. You may need to resolve a few wires that go between the 1FZ-FE ECM and the transmission TCM.

 

[DT80series]

Go nv4500 and split case.

 

[ThreeEyedBandit]

I went the longbow method with my stock A442. Currently manually shifting it(tcc included). If you go this way make sure you have the stall lowered in the convertor, I didn't and wish I had. If i did it again, I would go with the NV4500 and split case. Easy peasy.

Also why do you say with the split case you need to swap the axle out? I cant figure why you would need to do this.

Matt

 

[Beau Diddly]

Longbow's approach should also work for your A442F tranny which, in my opinion, is a better tranny than the A440. You may need to resolve a few wires that go between the 1FZ-FE ECM and the transmission TCM.

Will the A442F or A440 be able to hold up to the torque of the 4BD? What would the towing capacity of either stock tranny be? I would assume Longbow's modification would address these concern.

When I was considering the NV4500 and split case, I was also considering the part time 4WD option which I like, less wear and tear. However, I would loose my anti-lock breaks if I go this route. This is all good info, thanks.

 

[DT80series]

Both threeyedbandit and myself have A440 and A442's in our swaps both of us have recommended going with an NV4500 and split case. The Toyota autos are great transmissions and have no issue handling my engine turned up. The issue is the converters and transmissions suck up so much power and load the engine in a way that makes it take a lot to get the most out of the engines power.

The ABS issue can be overcome by marks ABS relocation kit. So it's a non issue.

 

[Adam R]

I'll third the NV4500, although I'm happy with my 4L80E tranny. It's fully adjustable and there is plenty of aftermarket support for that tranny, however it's an expensive way to go due to the number of adapters required (2) and need for an aftermarket tranny controller. If I were to do it again, I should have put the NV4500 and splitcase I originally sourced for my project. I sold my NV4500 about a year ago, but they can be found for around $1000.

Adam

 

[astr]

Will the A442F or A440 be able to hold up to the torque of the 4BD? What would the towing capacity of either stock tranny be? I would assume Longbow's modification would address these concern.

When I was considering the NV4500 and split case, I was also considering the part time 4WD option which I like, less wear and tear. However, I would loose my anti-lock breaks if I go this route. This is all good info, thanks.

I can't comment on the NV4500 as I've no experience with that transmission.

A variant of the A442 (AW450) is used in the newer Isuzu box trucks behind the 4HE1 (4.8 liter) and 4HK1 (5.2 liter) diesels so you should not have any problems with towing capacity. Seems like the problem that people have encountered is finding a torque converter to match the engine's torque curve.

 

[coog]

Here's a vote against the NV4500. We have one in our Scout. The steps between the gear are too steep for an urban environment, leaving you either winding out or lugging. Not a problem on the highway or off-road, but not well suited to 30-40 mph. Our Scout has 3.54 gears.

 

[DT80series]

I have driven a few, the Cummins I drove with a NV4500 was easy, did not feel I was lugging or winding it out. It is a engine that has gobs of power down low though. The other I drove was a 93 GM with the granny low first and big steps in the gears. The grind them till you find them feel of the gear changes sucked too on the early one.

If I keep my truck I will probably swap in an NV4500.

OP if you are stuck on an auto I will have a full bolt in setup when they time comes.

 

[Beau Diddly]

Good discussion that's leading me back to my first thought. I try to keep my mind open to a better idea, but it looks like all roads are coming back to the NV4500. I just wish there were better bolt-up option for the 4BD, but I haven't heard of a good Isuzu tranny with O/D that matches.

Speaking of keeping things stock, should I go with the NV4500, what are the thoughts of keeping my stock T-case? I know everyone goes with the split case, but now that there's an adapter option for the HF2AV, would it not be advantageous?

 

[DT80series]

I would be great to connect to the AWD t case. I would do it, but all I have done hear talk of it. I would want to see one working first. One guy on mud was saying he ordered one months ago and it was only 3 weeks away but never heard anything from him.

At this stage the salute case is a sure thing from a known good supplier. Sending $800 to get a guy with a spotty Rep to make you one is a bit sketchy to me.

 

[Adam R]

If there is an option to use the factory 80 series xfer case, go that route. That way you don't have to deal with the extra levers and linkages of the splitcase. Keep it in the stock location if you can so you don't have to modify your driveshafts.

Adam

 

[Beau Diddly]

I would be great to connect to the AWD t case. I would do it, but all I have done hear talk of it. I would want to see one working first. One guy on mud was saying he ordered one months ago and it was only 3 weeks away but never heard anything from him.

At this stage the salute case is a sure thing from a known good supplier. Sending $800 to get a guy with a spotty Rep to make you one is a bit sketchy to me.

That's Morgan, his mud name is mryangel or something like that. He received the adapter (basically a new mainshaft machined to fit the HF2AV) 2 or 3 months ago. Last I remember reading, he was waiting to get his 6BT back and was ready to start fitting everything... I'm watching it close, but he's been slow rolling the project. I've read all the issues about Dustin on this board and Mud, I spoke with him as well regarding the adapter. My take on it, he's a much better machinist than he is a businessman, probably a raging case of ADD. Too much detail to go into, but if this adapter works out for Morgan, I won't mind doing business with Dustin provided expectations and timelines are mutually agreed prior to payment through a credit card.

Again, I'm only leaning this direction, I'm always open to other suggestions.