That's one of my favorite things about the 14b FF.
CK5
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The Green Grendel
- Thread starter campfire
- Start date
Cool. I had originally measured the length of just the TH400, rather than including the adapter. So I originally thought I was 1.5" long rather than 3/4" short. I spotted the error while posting up the pictures. Not sure if that would have been a problem, but it sounded like a much smaller one when the difference cut in half.
The ease of maintenance is why I decided to keep & rebuild the 14BFF instead of swapping back to stock axles. I'm not particularly concerned with the strength of 1/2-ton axles, but the maintenance is just simpler on FF axles.
When the Suburban needed a new rear pinion seal, I decided that swapping in the 14BFF was funner than tearing apart and rebuilding the 10-bolt would have been. It probably took a little bit longer, but I'm still happy with it. And future pinion seal replacements should be a whole bunch easier.
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Tranny question:
I'm thinking about rebuilding the NV4500. I'm also thinking of not bothering with a rebuild.
Is there an easy way to spin it up to speed and see how well it shifts through the gears? I'd love to chuck the input shaft up in my drill, but the shaft diameter is a bit larger than my 1/2" chuck. Otherwise I'm not sure how I'd get it to spin faster than hand-cranking speed.
FWIW, it shifts into each gear and the output shaft responds appropriately.
I'm thinking about rebuilding the NV4500. I'm also thinking of not bothering with a rebuild.
Is there an easy way to spin it up to speed and see how well it shifts through the gears? I'd love to chuck the input shaft up in my drill, but the shaft diameter is a bit larger than my 1/2" chuck. Otherwise I'm not sure how I'd get it to spin faster than hand-cranking speed.
FWIW, it shifts into each gear and the output shaft responds appropriately.
From what your pics show, does this mean you can take the pedal assembly off any 85-91 truck (with hydro clutch) that has vacuum brakes and make the pedals work with the hydroboost brake setup? As far as I knew you could only use the assembly off a hydroboost if you were installing on a hydroboost truck (or vacuum assembly if installing on a truck with vacuum brakes). If this is the case, it will make my life a whole lot easier to find a pedal assembly as I am doing similar to what you are doing with my crew cab (has th400 now and will swap to NV4500).
You can use normal vacuum pedals with hydroboost (and vice versa) in at least 3 ways:
1) drill a new hole and use a new pin in the hydroboost spot
2) get a set of pedals with both holes (like mine) and move the pin (thanks to @sweetk30 for pointing this option out)
3) swap your existing automatic pedal into the manual pedal bracket and cut it off to be the appropriate size (this is what I ended up doing).
The pivot distance isn't hugely different. It might work out well enough just using the "wrong" location (just guessing, I haven't tried this). You'd have less leverage and shorter travel if you used vacuum pedals on a hydroboost truck.
Aside from the pin location, the pedals are dimensionally identical, so they can be swapped back and forth. Hydroboost pedals come with a return spring and a little cover. I swapped this across with no issues. As detailed in the pictures, 2 of the 4 studs on the pedal bracket are reversed for hydroboost trucks (no idea why).
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This is awesome to know! Thanks. Makes my life that much easier to find the right pedal assembly.
Cool! Glad to help clarify that. Option #3 didn't occur to me until I sat down with it and started comparing pedals...
Update for the last fortnight: Not much to report. I finally sneaked back out to work on it tonight for a few minutes. Tapped the bolt holes drilled into the face of the NV4500 (for the bell housing). And then found out that the bolts I have are too short. 
So not much to report. Doesn't even warrant a picture. But progress is slowly being made. I do now have use of a tranny jack, so that should make life much easier when the tranny finally comes out.
So not much to report. Doesn't even warrant a picture. But progress is slowly being made. I do now have use of a tranny jack, so that should make life much easier when the tranny finally comes out.
Last night I got out there again for a couple of hours. Started out tightening down the 3/8-24 bell housing bolts. 2 of them promptly stripped out, and I'm not satisfied with how well the others are grabbing. My threads are too loose (perhaps I used too large a drill bit originally), and the short threads on the fine-thread bolts just aren't grabbing enough metal.
So I'm stepping up to 7/16 bolts and switching to coarse thread. 7/16 is the size of the original bolts, so I now have to drill out the threads from the bell housing (I was trying to keep the bell usable if a future need ever arises). Back to the hardware store again...
So I'm stepping up to 7/16 bolts and switching to coarse thread. 7/16 is the size of the original bolts, so I now have to drill out the threads from the bell housing (I was trying to keep the bell usable if a future need ever arises). Back to the hardware store again...
But in other news, the TH400 is now out. 
Pretty sure this didn't help the shifting problem:
And the previous maintenance crews didn't do a fabulous job, either. Here I'm missing a bolt hole:
I've heard some folks declare that CUCVs must have had pristine maintenance "because they're military trucks." Others swear that the military's maintenance record is utterly shoddy. I'm leaning toward the second opinion as I get further into mine.
Oh...the 2 top bell housing bolts were loose. I think a majority of the bolts I've removed during this project were out of spec.
Pretty sure this didn't help the shifting problem:
And the previous maintenance crews didn't do a fabulous job, either. Here I'm missing a bolt hole:
I've heard some folks declare that CUCVs must have had pristine maintenance "because they're military trucks." Others swear that the military's maintenance record is utterly shoddy. I'm leaning toward the second opinion as I get further into mine.
Oh...the 2 top bell housing bolts were loose. I think a majority of the bolts I've removed during this project were out of spec.
I am encouraged, though. I think I've found my fluid leak, and that leaky hose was probably the shifting problem. It would shift occasionally, so I know the shifting mechanisms are functional. Sounds consistent with a vacuum leak to me.
So this tranny may yet have a life in some project somewhere.
So this tranny may yet have a life in some project somewhere.
Sounds like you still have a decent TH400, that's worth keeping around for sure.
So...now I'm at a decision point. The bell housing will be on soon, the transfer case seems fine. Funding is minimal for this project, so I'm not preemptively tearing stuff down. The tranny is in unknown condition (aside from spinning the input with my fingers). What (if anything) do I bother tearing apart and inspecting before installing this case?
Yeah.
I have the TH400, the driver-drop t-case, and 3 or 4 spare axles. All I need is an engine & frame and I'll have something. Not sure yet what I would build. I have at least 2 trucks between now and then. But I'm pretty good at coming up with weird uses for mechanical stuff. 
The misbehaving 700R4 in the Suburban...probably not such a great candidate for a project.
Bad tranny! Bad!
Boy, if I had a nickel...
Boy, if I had a nickel...
No kidding!
...it would probably be worth more than my tranny.
Don't sell spare parts unless you really need the money.... I always find a use for my parts after I have sold them!
I will sell unneeded parts for the right price. This tranny is pretty cheap to replace, and I don't have plans for it (I'm enough of an efficiency nut that I'm not likely to ever want it on the road again). So It'd be pretty easy to talk me out of it if selling it would generate enough funding to buy the next part that I actually do need. I'm not that keen on deliberately stockpiling parts, either. It seems that the pile just keeps growing and growing and growing. Pretty soon it's gonna drive me out of house and home!
Other parts (like my spare CUCV brushguard) I am much more attached to...
Fair enough!
And good for you keeping the 6.2 diesel alive in all your rigs!
That's cool!
And good for you keeping the 6.2 diesel alive in all your rigs!
That's cool!
