NP242 Question
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- Jon1097
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NP242 Question
What are the differences between the military and civilian NP242? I have a civilian 4l80e and there's a civilian np242 on epay for sale ($400). I was planning on going 24v with my wiring but was curious on the civilian and military differences. Thanks. -Jon.
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Re: NP242 Question
I am elbow deep in rebuilding 2 NP242 cases and here is what I found so far. I am converting 2 military spec ones to civi style...
The military has 24v switches
The military case, while having the same casting New Venture part number doesn't have the T/C switch drilled into it (near the coolers)
The retainer piece is different
The civi uses a tone ring and the military uses a purple worm gear thingy
Otherwise I compiled a really exhaustive list of all the parts and just about all the internals are the same
I am sure I am missing something but I am about 3/4 of the way thru the teardown and parts list. I know Brad converted a civi to milspec case for his A2 truck.
I also found that the military used 2 different NP242 transfer case designs, the A1 and A2. The A1 has 27 splines and the A2 used 32 (same as the civi). the housing and shafts are different. Also the civi transfer case was beefed up after 96 so watch for the year you have.
If you have any other questions let me know. Also unless that $400 is is really good shape you will burn about $400 in parts to fix it back up (w/o major shafts and planetary changes). you can get a rebuilt one for $1000 on the web.
The military has 24v switches
The military case, while having the same casting New Venture part number doesn't have the T/C switch drilled into it (near the coolers)
The retainer piece is different
The civi uses a tone ring and the military uses a purple worm gear thingy
Otherwise I compiled a really exhaustive list of all the parts and just about all the internals are the same
I am sure I am missing something but I am about 3/4 of the way thru the teardown and parts list. I know Brad converted a civi to milspec case for his A2 truck.
I also found that the military used 2 different NP242 transfer case designs, the A1 and A2. The A1 has 27 splines and the A2 used 32 (same as the civi). the housing and shafts are different. Also the civi transfer case was beefed up after 96 so watch for the year you have.
If you have any other questions let me know. Also unless that $400 is is really good shape you will burn about $400 in parts to fix it back up (w/o major shafts and planetary changes). you can get a rebuilt one for $1000 on the web.
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Re: NP242 Question
Did you use a spreader to get the parts out of the casing?
Jason
Jason
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Re: NP242 Question
didn't need a spreader, just removed all the snap rings. Isn't the spreader for the diff?Action wrote:Did you use a spreader to get the parts out of the casing?
Jason
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Re: NP242 Question
The tail-shafts are different to accommodate the speed sensor - the military tail-shaft has a much larger hole for the mechanical worm drive mechanism.doberer wrote:[SNIP]
The civi uses a tone ring and the military uses a purple worm gear thingy.......I also found that the military used 2 different NP242 transfer case designs, the A1 and A2. The A1 has 27 splines and the A2 used 32 (same as the civi). the housing and shafts are different. Also the civi transfer case was beefed up after 96 so watch for the year you have.
There was a upgrade to the t-case as mentioned where some of the internals and splines were changed around 95/95 on the civvie side. Any 97 and up Civvie with the right tail-shaft should work. There was a late 2000/2001 recall and mod to the civvie t-case cooling loop where the loop would crackand the dreaded "vampire" would strike - sucking the ATF out of the tranny. The mod added an additional mounting tab to the cooler loop to prevent vibration cracks. I don't know if the military loops got that mod too.
Cheers,
Clarke
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Re: NP242 Question
Correct. My bad. I have been working on my diff lately. I guess I just carried that into this post not realizing it is the T/C. Oops.doberer wrote:didn't need a spreader, just removed all the snap rings. Isn't the spreader for the diff?Action wrote:Did you use a spreader to get the parts out of the casing?
Jason
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Re: NP242 Question
It may also depend on what era you are trying to match to. Some of the Special Forces trucks ran with the electronic speedometer which I thought required some of the civy parts.
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Re: NP242 Question
Based on the info that Brad posted when he found the sender for the electronic speedo's, the drive assembly uses the same tail-shaft athe mechanical speedo. Here is his post: http://www.g503.com/forums/viewtopic.ph ... ad#p780639ragman wrote:It may also depend on what era you are trying to match to. Some of the Special Forces trucks ran with the electronic speedometer which I thought required some of the civy parts.
Cheers,
Clarke
- dunsbr
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Re: NP242 Question
***UPDATE***
I found another speed sensor for the Humvee.
I picked one up on my last trip to the US.
I'll post some pic's of it (and part numbers) when I get back home on the weekend
Cheers
I found another speed sensor for the Humvee.
I picked one up on my last trip to the US.
I'll post some pic's of it (and part numbers) when I get back home on the weekend
Cheers
Brad Dunstan
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
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Re: NP242 Question
Brad! You've been holding out on us.....dunsbr wrote:***UPDATE***
I found another speed sensor for the Humvee.
I picked one up on my last trip to the US.
Cheers,
Clarke
- dunsbr
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Re: NP242 Question
Who me?!?
Cheers
Cheers
Brad Dunstan
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
- dunsbr
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Re: NP242 Question
Hi Guys,
Here's the different type of HMMWV electronic speed sensor I picked up in the US on my last trip.
Cheers
Here's the different type of HMMWV electronic speed sensor I picked up in the US on my last trip.
Cheers
- Attachments
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- IMG00604-20090619-1735.jpg (42.15 KiB) Viewed 2103 times
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- IMG00607-20090619-1735.jpg (39.39 KiB) Viewed 2102 times
Brad Dunstan
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
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Re: NP242 Question
Could the pictures be any blurrier?
How does it work? Gear drive or inductive? Is this an alternate part to what you posted before or a different setup to drive the electronic speedo?
Cheers,
Clarke
How does it work? Gear drive or inductive? Is this an alternate part to what you posted before or a different setup to drive the electronic speedo?
Cheers,
Clarke
- dunsbr
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Re: NP242 Question
Hi Clarke,
Sorry, I took them in the workshop at night.
How are these?
As you can see, the sender simply screws on to the standard military Humvee geared speedo drive in place of the cable.
Cheers
Sorry, I took them in the workshop at night.
How are these?
As you can see, the sender simply screws on to the standard military Humvee geared speedo drive in place of the cable.
Cheers
Brad Dunstan
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
RHD '87 M1026
(with 4L80E Trans, 242 T/case, 12K hubs, CTIS, A2 wiring, Air Con, A2 ebrake, 9k Winch,
Serpentine Belt Accessory Drive & Eaton e-lockers)
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Re: NP242 Question
Part numbers unreadable.
Where did you get it? What about the harness up to the speedo?
Where did you get it? What about the harness up to the speedo?
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