Author Topic: 77 chev. NP203 4X4 conversion  (Read 14460 times)

Offline copekyle

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77 chev. NP203 4X4 conversion
« on: November 23, 2007, 03:49:42 pm »
Ok guys... I'm new here and I just bought my grandpa's 1977 chev with a 400 CID and NP203 tranny.  It has 84000 original miles and so it's in mint condition.  What I am wondering is what would it take to convert the full time four wheel drive to part time.  I've been reading everywhere and seen there are a few different kits for this.  There are no locking hubs on this truck right now.  So can someone suggest a kit that has everything I need to do this.  I understand that I need to change some things in the case but I don't know if I would still need locking hubs if I convert the case.  Someone point me in the right direction for a complete kit.

Thanks!!!
Kyle

Offline KojaK 79k10

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Re: 77 chev. NP203 4X4 conversion
« Reply #1 on: November 23, 2007, 04:00:26 pm »
you have to have locking hubs if you do to part time kit. i have done the kit and its nice but for the money i wouldn't do it again. (very labor intensive) google the NP203 part time kit and go to the coloradoK% website  there you Will find a very nice review with great instructions on how to do it. just read it and you will be overwhelmed.
77 Chevy swb "race truck"

*SOLD* 79' k10 Silverado SWB "Kojak"
truck is gone but not forgotten, worst thing I ever did was sell this truck and I regret it everyday.

Offline VileZambonie

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Re: 77 chev. NP203 4X4 conversion
« Reply #2 on: November 24, 2007, 08:17:11 am »
I think it's a fairly simple conversion.

The transfercase kit is easy to install.

replacing the hubs with manual lockers is pretty easy too. Make sure you have hex key wrenches, a spanner socket, snap ring pliers, a pick tool set and some shop towels.

http://www.coloradok5.com/milemarkerpt.shtml
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Offline Fordeatinz71

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Re: 77 chev. NP203 4X4 conversion
« Reply #3 on: November 24, 2007, 07:19:37 pm »
yea, it's not a hard conversion.  if you are "overwhelmed" by this then there probably isn't a whole lot you can do on a vehicle.  this rates about a 3-4 out of 10 as far as job difficulty.  just take your time, read the directions and you'll be able to pull it off...
1991 Chevy Silverado K1500 ECSB, 350, 700R4 w/shift kit, 3.42's, exhaust work...
1983 GMC Sierra K1500 SWB-sold :(

Offline copekyle

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Re: 77 chev. NP203 4X4 conversion
« Reply #4 on: November 25, 2007, 04:50:01 pm »
ok.  So which kit do I get?  I do not have locking hubs on the truck now.  Can I put on just the kit without locking hubs?  Can someone recommend a good place to buy the kit.  Of course I want the best price and the  part stores in my small town don't seem to EVER have the best price!

Thanks

Offline KojaK 79k10

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Re: 77 chev. NP203 4X4 conversion
« Reply #5 on: November 25, 2007, 07:53:09 pm »
the best kit is the milemarker kit and that is just the kit w/out hubs. you can get this through summit racing for $44.39. It does not come with hubs but thats ok, I only use Warn hubs because they rarely ever break and i have had no problem. you can get a set of hubs for about $90 compared toe the mile marker hubs at over $150. (the website link that Vile posted is the best instructions you can get) follow these instructions and not so much the instructions in the kit. read the link and you will see
77 Chevy swb "race truck"

*SOLD* 79' k10 Silverado SWB "Kojak"
truck is gone but not forgotten, worst thing I ever did was sell this truck and I regret it everyday.

Offline chevy754x4

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Re: 77 chev. NP203 4X4 conversion
« Reply #6 on: November 26, 2007, 08:16:30 am »
I would have to agree about the Warn hubs.  I know lots of guys who run those with very good results.  As far as not putting the manual locking hubs on... you could get by without them.  However doing so would eliminate most of the reasons for converting the NP203 to part time as all the "stuff" in the front diff will still be spinning as you drive instead of just the wheels and brake rotors.

Offline Hank Hill

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Re: 77 chev. NP203 4X4 conversion
« Reply #7 on: November 26, 2007, 01:06:47 pm »
Isnt there lubrication problems with converted to part time 203 cases? I was always told there was and to avoid buying a truck or 203TCs that where coverted.

Offline copekyle

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Re: 77 chev. NP203 4X4 conversion
« Reply #8 on: November 26, 2007, 02:04:36 pm »
I've researched that out and there is a small problem with lubrication BUT with the mile marker kit, they recommend switching to 4-wheel drive every 100 miles to lubricate.  I've also read that when filling the transfer case with oil, to jack up the back tires so the case will overfill slightly and everything will be lubricated just fine.


Ok, so I can go with the WARN hubs.  Can someone find me a part number for which ones to buy?  And give me a good idea of where to buy them?

Thanks

Offline Captkaos

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Re: 77 chev. NP203 4X4 conversion
« Reply #9 on: November 26, 2007, 05:39:36 pm »
On a converted T-case you just have to put it in 4wd every so often and drive as stated.

Offline copekyle

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Re: 77 chev. NP203 4X4 conversion
« Reply #10 on: November 27, 2007, 01:16:11 pm »
Ok, so I can go with the WARN hubs.  Can someone find me a part number for which ones to buy?  And give me a good idea of where to buy them?

Offline VileZambonie

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              ⌠ŻŻŻŻŻ'   [☼===☼]
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline 1976Scottsdale

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Re: 77 chev. NP203 4X4 conversion
« Reply #12 on: December 02, 2007, 05:22:20 pm »
I think it's a fairly simple conversion.

The transfercase kit is easy to install.

replacing the hubs with manual lockers is pretty easy too. Make sure you have hex key wrenches, a spanner socket, snap ring pliers, a pick tool set and some shop towels.

http://www.coloradok5.com/milemarkerpt.shtml

Lots of shop towels.  and liquid refreshment. ;D

Offline Hank Hill

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Re: 77 chev. NP203 4X4 conversion
« Reply #13 on: December 12, 2007, 12:44:16 pm »
Why not go with a 203/205 doubler? Then you will have 2H, 2L, 4H, 4L, plus you can engage with the other lever either just your front or rear driveshaft.
If you already have a good 203T/C then your a third of the way there already.

Offline KojaK 79k10

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Re: 77 chev. NP203 4X4 conversion
« Reply #14 on: December 14, 2007, 08:49:21 pm »
the doubler kit is bad but unless you like to hard core wheel your truck its not so practical. you could get a NP205 for less then that and have REAL part time 4wd. but thats my opinion. the part time kit isn't all that hard and its cheap if your on a budget. as for the locking hubs, go with warn premium hubs if you can, there just that much better then standard warn hubs.
77 Chevy swb "race truck"

*SOLD* 79' k10 Silverado SWB "Kojak"
truck is gone but not forgotten, worst thing I ever did was sell this truck and I regret it everyday.