Author Topic: 12 bolt swap.  (Read 55829 times)

Offline ccz145a

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Re: 12 bolt swap.
« Reply #45 on: August 13, 2008, 01:06:03 pm »
Quote
CCZ, when you swapped your axle, what was your method of getting the shocks back on to their mount? They have to be compressed I know. I was under there last night cleaning the area up in prep for the new axle which should be going in tonight I hope   and I tried compressing the shock myself but it didn't want to seem to budge. Should I use the floor jack to compress it enough to get onto the shock mount?

I just pushed... steady push, it finally started compressing. once it starts moving, you got it. have your bolt ready before you start and compress it more than needed, it takes two hands, then when it expands, guide it towards the mount and throw the bolt in. I had to do this more than once to get the hang of it.

Couldn't have done more than one truck, though. Need to eat your Wheaties  :D
1975 C10 Silverado LWB, 454CID, TH400, 10bolt 3.42
11MPG Downhill w/tailwind (but there ain't no hills here)

Offline SUX2BU99

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Re: 12 bolt swap.
« Reply #46 on: August 13, 2008, 01:40:16 pm »
lol  Just muscle it in eh? Alright, I'll give it a whirl. Thanks.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Captkaos

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Re: 12 bolt swap.
« Reply #47 on: August 13, 2008, 02:40:21 pm »
You should be able to compress it with your hands as CCZ said.  Once you overcome the initial "umph".  Technically you shouldn't leave them extended though...

Offline SUX2BU99

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Re: 12 bolt swap.
« Reply #48 on: August 13, 2008, 02:45:16 pm »
Right on. I didn't give it too hard of a try last night but I will be tonight or tomorrow. They've been fully extended for less than a week so hopefully that hasn't damaged them. My time is on the short side of supply!
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline SUX2BU99

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Re: 12 bolt swap.
« Reply #49 on: August 17, 2008, 11:10:19 pm »
DONE!!

I gotta say that putting it in was a TON easier than getting it out! I rushed to get it all together by Friday afternoon to take it to the Friday night street legal drags at Mission Raceway. I got very close to getting it done in time but not 100%  :-\ Oh well, in 2 weeks there is another race. I did get it driveable though. Everything went in well except for:
- pass side parking brake cable attachment at the drum. I was getting frustrated trying to get it clipped in, it was hot out and I had been hard at it for about 7 hours getting the diff in so I tie strapped it to the frame and will get to it later. I got the drivers side done though
- had to put the non-turned drums on since my freshly turned drums would not fit onto the shoes. I would have to force them and they'd drag a lot even if they did go on. I can't figure out why 1 pair of drums is a smidge smaller than the other. I backed the brakes off and I did drive it like that. No funny noises or vibrations though but I will get those drums turned.
- the new diff's shock mount bolts were rusted on their super tight. One bolt broke so that was okay, but the other would NOT go anywhere. The bolt head started to turn inside the socket. So I had to cut it off at the nut and my new, never-used air body saw wasn't working well and eventually quit, so I had to use a hack saw and broke 3 blades. I got it off though so whatever.
- the new grade 8 bolts I got for the shocks were too big I found out when trying to put them so had to do a parts store run and get smaller bolts
- I bought new u-bolts and hardware and the day I was supposed to pick them up, they forgot to leave them outside for me, so I had to wait another day for them

Otherwise it went well :) Torqued everything up. I drove it Friday and today and it's running great. The 3.40 gears are a nice improvement over the 2.76's for getting the motor into it's powerband. Now when I stomp on it from idle or a 1000 rpm roll, it seems the converter will flash to 2500 and then go. Before it might flash at 1800 or so it seemed. Bad news it seems the posi isn't all that tight  :(  Good news it will pretty much light up at least 1 tire from an idle stomp, if the carb doesn't stumble so bad that it stalls. I even had it light 1 tire and some of the other and then spin and hold it right into 2nd gear. If it brake-torque it anywhere past 1500 both tires start to spin. I'll have to work on getting my launch right.

So it's been about 2 months since I bought that very rusty diff from a bone yard for $150 but it's now all painted and in, with new brakes and u-bolts and I have 1 more project under my belt.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline SUX2BU99

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Re: 12 bolt swap.
« Reply #50 on: August 19, 2008, 02:15:40 pm »
Here are some pics. I have descriptions and more pics listed on my page http://www.cardomain.com/ride/3001366/2

About to come out


Old diff out


New diff guts showing limited slip unit


New diff in

85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline 06gsxrman1000

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Re: 12 bolt swap.
« Reply #51 on: August 19, 2008, 02:33:23 pm »
good job man
Three may keep a secret, if two of them are dead.
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Offline Captkaos

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Re: 12 bolt swap.
« Reply #52 on: August 19, 2008, 02:54:14 pm »
Ahhhhhh, pics...

Offline comp

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Re: 12 bolt swap.
« Reply #53 on: August 19, 2008, 03:59:56 pm »
looking good  ;D

Offline Jim Rockford

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Re: 12 bolt swap.
« Reply #54 on: January 06, 2010, 03:31:11 pm »
Just so you know, the gov lock isn't really meant for on road lockups , if you abuse it even slightly it will come apart. There is a reason they Call em the Timex posi...cause its a time bomb waiting to explode.
1973 k20 Camper special
1980 k20 custom deluxe
2004 Crown Vic LX sport

Offline SUX2BU99

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Re: 12 bolt swap.
« Reply #55 on: January 06, 2010, 05:12:50 pm »
Since I wrote this, I've taken that diff out and just put in another 3.40 Gov-lok. This unit apparently works fine though. The last one did not and I went through a whole schmozzle of new Eaton Posi, 3.73 gears, multiple failures, blah blah blah. Anyway, the old Gov-lok was seized and unworking. It went through about 20-30 dragstrip passes and burnouts with no issues at all but it wasn't working right anyway. I am a little worried about blowing this 'new' one up but I've heard of the good ways to blow up Gov-loks and I won't be doing that (like right-turn throttle stomps or one tire spinning on gravel and then hitting pavement where it grips suddenly).

My truck doesn't seem to like burning the tires off from an idle so it might just be fine.
85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Captkaos

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Re: 12 bolt swap.
« Reply #56 on: January 06, 2010, 05:14:51 pm »
not to mention this post is like 1.5 years old..

Offline Jim Rockford

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Re: 12 bolt swap.
« Reply #57 on: January 07, 2010, 08:46:06 am »
Just bringing it up for everyone elses info.
1973 k20 Camper special
1980 k20 custom deluxe
2004 Crown Vic LX sport

Offline VileZambonie

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Re: 12 bolt swap.
« Reply #58 on: January 08, 2010, 04:37:39 pm »
There is a reason they Call em the Timex posi...cause its a time bomb waiting to explode.

Doesn't Timex take a lickin and keep on tickin?
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Offline NevadaNeal

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Re: 12 bolt swap.
« Reply #59 on: January 14, 2010, 09:27:17 pm »
I grenaded the pozi in my 12 bolt to..rebuilt the rear end then sold the engine out of the truck..lol if you need another i have one sitting here..thought it is 6 lug.