Ok, strike 3 for me.
CK5
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The Great Smaug
- Thread starter campfire
- Start date
Ok, strike 3 for me.
My understanding of hydroboosts: they are basically the same. I think there are only two different main bodies. The differences? The input rod/piston assemblies came in two sizes that must match the HB body. Newer ones may have larger openings for larger master cylinder options. The input rod assemblies also have different ways the pedal rod attaches to it. 70s models used flare fittings and they switched to o-rings around 80 or so. The master cylinder output rod came in two lengths. They are very obvious differences, especially if you look at how recessed the master cylinder's input piston is. Most are the shorter one. Accumulators vary...I've seem four or so different ones. The spool valve and body are a matched set. Maybe I'm wrong, maybe there are different valving options but I could not find that info. It SEEMS that the main difference in part numbers is due to pedal rod length and output rod length. New/reman units don't come with the firewall bracket. I spent a lot of time looking into this before I did my swap.
My hydroboost came off a 94 g20 van. Someone left just a square body bracket and pedal on a 70s chevy truck so I pieced them together. I removed the big nut from the bracket with my front axle nut socket. It wasn't pretty, but it came off with an impact and went on the other bracket with thread locker. The correct part number for the proper tool is J-24554. I did, however, have to cut the pedal rod and thread it and add a coupler nut to be able to adjust it to my pedal since it wasn't a square body rod. If the rod is in place, you won't be able to get a socket on that nut, but if I recall, yours was falling out anyway. The rebuild kit also comes with the parts to secure the pedal rod back in the new input rod assembly. I am fairly certain there are only two different sizes of that assembly since there are only two sets of o-rings in the rebuild kit. As long as the input rod assembly is the same size, it should work fine. No nicks allowed on the piston though...it'll leak.
Hope this helps you understand your options. I have some pics in my build too.
My hydroboost came off a 94 g20 van. Someone left just a square body bracket and pedal on a 70s chevy truck so I pieced them together. I removed the big nut from the bracket with my front axle nut socket. It wasn't pretty, but it came off with an impact and went on the other bracket with thread locker. The correct part number for the proper tool is J-24554. I did, however, have to cut the pedal rod and thread it and add a coupler nut to be able to adjust it to my pedal since it wasn't a square body rod. If the rod is in place, you won't be able to get a socket on that nut, but if I recall, yours was falling out anyway. The rebuild kit also comes with the parts to secure the pedal rod back in the new input rod assembly. I am fairly certain there are only two different sizes of that assembly since there are only two sets of o-rings in the rebuild kit. As long as the input rod assembly is the same size, it should work fine. No nicks allowed on the piston though...it'll leak.
Hope this helps you understand your options. I have some pics in my build too.
Thanks for the info. Haven't decided which way I'm heading yet, but I'm leaning toward just buying the correct OEM part at this point.
Here's an apples-to-apples comparison of the actual rims that I am going to be running (trailer rims don't count). The one GM rim (left) is a different shade than the 4 Ford rims.
Paint them white.
Martin
Martin
Paint them white.
Matt
Matt
Paint them white.
James
James
Paint them white.
Greg
Greg
You guys are all silly.
Painting, when/if it happens, is a ways away at this point. The arrival of white stuff yesterday means that we're officially in wet winter mode now, so outside time will be falling off. Kinda like the paint would be if I sprayed them at our current temperature.
The main goal in shuffling wheels around was to get the smaller tires freed up for use on the Blazer. Painting stuff is really a distraction at this point. I have a tranny to fix first and also a suspension to redo.
Yesterday I went to buy this:
And it turned out that the seller still had the donor truck, too. So I spent an hour pulling off parts and left with much more than I had planned.
New parts:
Hydro bell housing
W-crossmember (So I don't hafta roadkill a trans mount next time).
32-spline NP208.
These are the 3 things I needed to pull off the NV4500-swap in this truck, so that is now in the plans. In a few months when weather breaks, that is.
But I also wound up with these other parts:
late-model SM465
Manual steering column & steering shaft
set of hydo-clutch vacuum-boost pedals
Front driveshaft
The 2-prong weatherpack connector that I couldn't find cheaply. I grabbed 2 of them, but upon getting home I found out that they aren't the same.
A speedometer cable (which has already been installed in the Blazer).
A hood release cable (Big Blue's has had a broken sheath since before I got it).
And a few odds & ends.
@78K30
And it turned out that the seller still had the donor truck, too. So I spent an hour pulling off parts and left with much more than I had planned.
New parts:
Hydro bell housing
W-crossmember (So I don't hafta roadkill a trans mount next time).
32-spline NP208.
These are the 3 things I needed to pull off the NV4500-swap in this truck, so that is now in the plans. In a few months when weather breaks, that is.
But I also wound up with these other parts:
late-model SM465
Manual steering column & steering shaft
set of hydo-clutch vacuum-boost pedals
Front driveshaft
The 2-prong weatherpack connector that I couldn't find cheaply. I grabbed 2 of them, but upon getting home I found out that they aren't the same.
A speedometer cable (which has already been installed in the Blazer).
A hood release cable (Big Blue's has had a broken sheath since before I got it).
And a few odds & ends.
@78K30
Wow! Nice score.
Yes it was. There was also a rear driveshaft, but I wanted the slip yoke to keep the 208 from gushing all over the place. He offered to cut through the U-joint so I could fit it into the vehicle, but next thing I know he was whacking the yoke with a maul to separate it. I did use the slip yoke to plug the hole, but it is shattered beyond using.
It was weird taking the dash apart and realizing that I had the bolt sizes & locations memorized. But after doing 4 sets of pedals and 6 columns, I'm starting to get better at it.
I will say this...the axles were gone and the frame was cut in half, so the speedo cable was wedged underneath the frame rail. The seller flipped the cab over for me to free up the cable, and I did all the dash work with the cab on its roof. Turns out that it's quite a bunch easier to do pedals & column that way. Not sure if I'll ever do things upside down again, but it was handy in this case.
mmmm I love me some SM465
mmmm I love me some SM465
You want it? It will be in the classifieds soon. If I'm going to go through all the work, I'm going to have at least 4 real gears instead of 3.
As I've said before, I'd rather have a real 5-speed, but the 4.5 speeds in the NV4500 will suffice. Running non O/D tranny in a 3.73 diesel rig with 33" tires would be miserable on the highway.
I'll probably kick myself but I'll pass on it, my other truck has the 833 it it anyways!
The 833 is an O/D tranny, so if you're looking for deeper gearing it might not be the worst swap out there, trading O/D for granny gear...
Buy them both!
The 833 is an O/D tranny, so if you're looking for deeper gearing it might not be the worst swap out there, trading O/D for granny gear...
Buy them both!
The goal is to run the 833 with 3.73's on 31's, I've already got 2 SM465 rigs I suppose a parts trans wouldn't be the worst thing ever!
I'm pretty good at collecting your money. Or, I would be, if any money actually changed hands.
Lemme know what you wanna do. If you want it, I should be able to pack it into the car like I did Greg's tranny. We'll be down there in a couple weeks.
Interesting. That 0.73 final drive ratio gives you exactly the same gearing/axle/tire combination that my Blazer is running. Except you're not running the diesel engine. This continues to reinforce my idea that the blazer is geared too lowly. On 31s I would be happier with 3.42 gears.
