Author Topic: 78 K10 shooting out of 4WD when driving  (Read 9465 times)

Offline xgruntusmc

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78 K10 shooting out of 4WD when driving
« on: January 02, 2014, 09:45:41 PM »
hey everyone, new guy here with a quick question.  I've got a '78 K10 4WD I bought a couple months back.  I haven't really gotten to use it that much but the two times now that I've put it in 4WD it works fine but the shifter will launch out of gear when I'm using it.  It's not making any noises (that I've been able to hear anyway), manual hubs and it'll go into 4WD without a problem, staying is the issue.   I believe stock it has 3.07 gears in it and i'm thinking that it's probably a gear issue and those need to be changed out (which i'm going to up to 3.73's) but i just wanted some other opinions on this matter.  also it's got the stock 350 four bolt main that i was going to strip, hot tank, bore 40, hone and build up, thoughts on this? i look forward to talking with y'all, take it easy
-Gib
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

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Offline Engineer

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Re: 78 K10 shooting out of 4WD when driving
« Reply #1 on: January 02, 2014, 10:15:54 PM »
What tranny, and transfer case?
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
1994 Chevy K-2500 4x4 C6P 5.7/4L80E
1979 Chevy K-30 4x4 4sp 4.10
1977 Chevy K-30 4x4 4sp 4.10 454

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Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #2 on: January 02, 2014, 11:30:45 PM »
transfer case
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline Irish_Alley

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Re: 78 K10 shooting out of 4WD when driving
« Reply #3 on: January 02, 2014, 11:36:05 PM »
first make sure its not hitting the sheet metal. sometimes they can seat into 4wd but the sheet metal will prevent them from locking in (best scenario)
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #4 on: January 02, 2014, 11:40:01 PM »
just so i'm clear here, the sheet metal on the floor in the cab?
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline Irish_Alley

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Re: 78 K10 shooting out of 4WD when driving
« Reply #5 on: January 02, 2014, 11:43:53 PM »
yes. it could be a bad mount causing the t-case to sag a little, then if you get on it it can move a little more and hit the sheet metal. or if someone made a 2wd cab into a 4wd and didnt cut the hole big enough. you can also try to adjust the linkage. if theses ideals dont work you might have to rebuild the t-case. what case do you have?
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #6 on: January 02, 2014, 11:50:00 PM »
i'm not positive what TC i have to be honest with you, i haven't gotten into it that much.  and it'll shoot out going slow not even getting on it.  it wasn't modified from a 2WD it has always been 4WD
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline Irish_Alley

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Re: 78 K10 shooting out of 4WD when driving
« Reply #7 on: January 02, 2014, 11:54:42 PM »
203 shift pattern
4Low lock
4Low
N
4High
4High lock

205 shift

4Low
N
2High
4High
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #8 on: January 03, 2014, 06:33:06 AM »
thanks for that information, with that being said i have the 205
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline dvdswan

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Re: 78 K10 shooting out of 4WD when driving
« Reply #9 on: January 03, 2014, 11:19:28 AM »
hopefully its the trans mount.   but does it only do it in 4HI or does it do it in 4LO as well?

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #10 on: January 03, 2014, 12:34:06 PM »
haven't even tried it in 4 low yet, but it does it without fail in 4 Hi i know that much.  like i said originally, i'm planning on changing out the gears to 3.73 anyway, but I was trying to find out if someone knew if there was another issue i should be expecting
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline dvdswan

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Re: 78 K10 shooting out of 4WD when driving
« Reply #11 on: January 03, 2014, 12:44:01 PM »
crawl under and see if the trans mount is bad, you my need to grab a prybar and see if it moves.  then check the cab, you can tell by unscrewing the boot cover and shifting in 4HI and see if it hits.

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #12 on: January 03, 2014, 01:12:01 PM »
dave thanks, i'll check it out today or tomorrow when i get a chance. also, sweet little truck you just got, i was looking for exactly that, but all the ones i found were in horrible shape, but i'll get some pics of my 78 K10 up shortly on here and PB for you to check out. i want that bucket seat set up you have though!!! lol
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline xgruntusmc

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Re: 78 K10 shooting out of 4WD when driving
« Reply #13 on: January 03, 2014, 04:23:50 PM »
here's the link, let me know if it works             http://s982.photobucket.com/user/Adam_Gilbeau/story/34521
"I prefer peace. But if trouble must come, let it come in my time, so that my children can live in peace."

http://s982.photobucket.com/user/Adam_Gilbeau/story/34521

Offline dvdswan

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Re: 78 K10 shooting out of 4WD when driving
« Reply #14 on: January 03, 2014, 05:32:04 PM »
clean looking K10.  I like the rally wheels.