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OK. Need help. Swapping a TH400 out and NV4500 in OBS truck.

A

Acesneights1

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I recently came into possession of an NV4500 from a 93 6.5TD complete. Clutch, bell housing everything. I can't use the transfer case as the drive shaft is on the wrong side but so far everyone is telling me the Case from the TH400 should bolt up to the NV4500. I hope so. Now onto the challenge. How my gonna make the clutch work ? I need a pedal assembly so if anyone has one, I got's cash. Also will the line from the 93 hook up to the master for an 85-87 ? Anybody know what side the slave is on with a SM465 setup ? Anybody ever attempt what I am trying to do ?
 
you are in luck! the only reason I remember these articles even being published was due to them being the only half realistic projects in the magazine around that time. plus the 6.2L probably had something to do with it.

here is the trans. swap article: http://www.4wheeloffroad.com/techar...n_5_speed_manual_transmission_swap/index.html

here is the case they hooked to it: http://www.4wheeloffroad.com/techarticles/drivetrain/131_0701_lomax_transfer_case/index.html

and here are some more articles they did on this awesome old girl:

http://www.4wheeloffroad.com/brandpages/chevy/131_0403_1986_chevy_1_ton_army_truck/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0404_1986_chevy_1_ton_army_truck_2/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0405_1986_chevy_1_ton_army_truck_3/index.html
http://www.4wheeloffroad.com/featuredvehicles/131_0405_1_ton_chevrolet_truck/index.html

and where he lost the seal and wrecked the trans.
http://www.4wheeloffroad.com/features/131_0901_1986_chevy_1_ton_army_truck_problems/index.html
 
also, to make searches a little easier, most forums rank the OBS at the GMT400 trucks so it is

OOBS: 73-87
OBS: 88-98
NBS: 99-06
NNBS: 07-current

I know, dumb system, but that seems to be the way it is.
 
GM Guy said:
you are in luck! the only reason I remember these articles even being published was due to them being the only half realistic projects in the magazine around that time. plus the 6.2L probably had something to do with it.

here is the trans. swap article: http://www.4wheeloffroad.com/techar...n_5_speed_manual_transmission_swap/index.html

here is the case they hooked to it: http://www.4wheeloffroad.com/techarticles/drivetrain/131_0701_lomax_transfer_case/index.html

and here are some more articles they did on this awesome old girl:

http://www.4wheeloffroad.com/brandpages/chevy/131_0403_1986_chevy_1_ton_army_truck/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0404_1986_chevy_1_ton_army_truck_2/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0405_1986_chevy_1_ton_army_truck_3/index.html
http://www.4wheeloffroad.com/featuredvehicles/131_0405_1_ton_chevrolet_truck/index.html

and where he lost the seal and wrecked the trans.
http://www.4wheeloffroad.com/features/131_0901_1986_chevy_1_ton_army_truck_problems/index.html
Click to expand...

Thanks. That answered some questions. although I will probably use the diesel bellhousing as I have one and the slave is on the pass side. I would think I could get some kind of line made up to mate that slave(93) to the master from the 86. I will use the NP208. As much as I agree that an NP205 is the bomb, I don;'t have one nor the bread to buy one. The NP208 will be fine. So far it doesn't look that bad except finding a set of pedals. I have changed them in the past. Not bad to pull the colum from an 86. No a/c so even easier.
 
yeah, I dont know what they were doing with the bellhousing. I am sure the diesel one would hold up just fine.

As far as the hydraulics, I dont know what they run for fittings, but I agree that it shouldnt be an issue to get one made. I wonder if inlinetube.com would work with you on a stainless one, but IDK how bad their pricing would be on a custom one.
 
GM Guy said:
if inlinetube.com would work with you on a stainless one, but IDK how bad their pricing would be on a custom one.
Click to expand...

Doesn't matter if they can make it...:D. What did have me curious was the crossmember they used. I wonder if I will need that with the 208 case or was that because of the 205. A TH700 crossmember should not be hard to find. Dave might even have his old one.
 
so you are looking for an OEM hydraulic clutch for the 73-87 style trucks? was anything changed to prevent the use of one from a crew cab 88-91? what all years did they come in? there is plenty of crap in this area that I could keep an eye out.
 
GM Guy said:
also, to make searches a little easier, most forums rank the OBS at the GMT400 trucks so it is

OOBS: 73-87
OBS: 88-98
NBS: 99-06
NNBS: 07-current

I know, dumb system, but that seems to be the way it is.
Click to expand...

Yup, dumb system, I prefer square body, gmt-400, gmt-800, & gmt-900. There are way too many year overlaps for the bodystyles.

Aces, I *might* be able to figure out what the thread dimensions are on the fittings for the hydraulics, will let you know.
 
GM Guy said:
so you are looking for an OEM hydraulic clutch for the 73-87 style trucks? was anything changed to prevent the use of one from a crew cab 88-91? what all years did they come in? there is plenty of crap in this area that I could keep an eye out.
Click to expand...

AFAIK as long as it's square body style, it should fit. I need hydraulic though. Pre 85 had zbar linkage which was actually better but I am not sure about retro fitting that to an NV4500. There are a few companies that make an aftermarket bell housing but they are for gassers and the diesel starter maybe an issue.
 
GM Guy said:
you are in luck! the only reason I remember these articles even being published was due to them being the only half realistic projects in the magazine around that time. plus the 6.2L probably had something to do with it.

here is the trans. swap article: http://www.4wheeloffroad.com/techar...n_5_speed_manual_transmission_swap/index.html

here is the case they hooked to it: http://www.4wheeloffroad.com/techarticles/drivetrain/131_0701_lomax_transfer_case/index.html

and here are some more articles they did on this awesome old girl:

http://www.4wheeloffroad.com/brandpages/chevy/131_0403_1986_chevy_1_ton_army_truck/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0404_1986_chevy_1_ton_army_truck_2/index.html
http://www.4wheeloffroad.com/brandpages/chevy/131_0405_1986_chevy_1_ton_army_truck_3/index.html
http://www.4wheeloffroad.com/featuredvehicles/131_0405_1_ton_chevrolet_truck/index.html

and where he lost the seal and wrecked the trans.
http://www.4wheeloffroad.com/features/131_0901_1986_chevy_1_ton_army_truck_problems/index.html
Click to expand...

You know, it's funny . After re-reading that article, those guys are morons. They actually at one point said, oh we could use a smaller starter from a gasser leading people to believe that that would actually work and why on god's green earth would you not just use a diesel bell housing. I would not be grinding out a bell housing. I think they made more of it than it is. My biggest unknown is whether my Transfer case will bolt up to the NV4500. Everything else I am reasonably sure will be workable. I can easily make any crossmember. The only other problem I could possibly see is the hieght of the tranny hitting the floor of the cab but again in that article they obviously knew nothing about those trucks. There is an imprinted line around the hump where you can cut out for the manual tranny. the trick would be to then get a removable floor pan from a truck with a stick. It seemed like those parts were so easy to get but then I forget how old I have become. I did many manual 4spd swaps and it was a piece of cake. One thing about GM, everything is interchangable on those older trucks. May need to use a few different parts but it will work. As long a I can bolt a RH transfer case to that tranny I know I can make the rest work. Of course now the guy I am getting the tranny from say he thinks it was hard to get into third....:mad2: I drove the truck before it blew up and don't remember that. He probably has no idea how to drive and or shift a diesel. AFAIK the NV4500 is pretty bulletproof.
 
Acesneights1 said:
Doesn't matter if they can make it...:D. What did have me curious was the crossmember they used. I wonder if I will need that with the 208 case or was that because of the 205. A TH700 crossmember should not be hard to find. Dave might even have his old one.
Click to expand...

The 700R4 and the SM465 used the same crossmember, even the same driveshafts and linkage setups(for the t-case). I have the crossmember from the 700R4 in there. It lined right up and bolted together.

The 700R4 and SM465 combos(trans and np208) are the same length which is why everything was interchangeable. I didn't know this going in, but it certainly made things easier.

Acesneights1 said:
Of course now the guy I am getting the tranny from say he thinks it was hard to get into third....:mad2: I drove the truck before it blew up and don't remember that. He probably has no idea how to drive and or shift a diesel. AFAIK the NV4500 is pretty bulletproof.
Click to expand...

The NV4500 likes to eat synchros over time. the 3rd gear one is the most popular one to bite the dust first, so he may be telling the truth.
 
Checked out that link. seems they have everything for rebuilding the tranny including a video. Has anybody done one ? Is it just change the parts and put it back together or do clearances and preloads need to be set ? I see they have a rebuild video for 30$. I'm gonna get a price on having the tranny freshened up. Might as well do it while it's out of the truck.
 
yeah, on that bellhousing, it was an aftermarket steel one. I presume use was for advertising dollars, so they modded it and blamed it on the diesel part of it. I would use a aluminum 6.5L bellhousing in a heartbeat.
 
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