Chevy Astro and GMC Safari Forum banner

Best way to get a Posi

6K views 35 replies 12 participants last post by  AstroWill 
#1 ·
Well, winter is coming, and I still have an open diff. My question is, what is easier/cheaper/best? A junkyard G80 axle, find a refurbished G80 axle, or get the internals and use my existing axle? Right now my right thumb/wrist is sprained, so I can't be lifting all that much, so a whole rear axle from a jy might be out, at least til I heal up better. Also, the p&p yards near me are kinda $$$. When some people go and post their costs for the parts they got, at mine they are 2-3 times more expensive. I'm also not sure about the reliability of the jy axle either.

I know my rear end is still pretty good, and I have a line on some brand-new internals for about $200. While I'm doing that, I figure I could replace the axle seals & check on the gear wear. Yes, new fluid too. My van is also my DD, so I can't be down with issues. I've done a bit of wrenching on vehicles, just haven't messed with a rear diff...yet. So any comments are welcome, I hope to have it done before the end of Nov.

Here's a pic of the internals.


-Andrew
 
See less See more
1
#2 ·
i saw the same craigslist ad for the posi, i allready have the same one so i don't need it.
my advice buy it, screw the local yards i used to work at a yard in slinger and i can't even walk and pull anything there anymore, if you wanted to pay a little bit for someone to help you out its not that hard to do.
 
#6 ·
Well Jim, I figured $200 for the internals, haven't priced the seals or fluid, so I wasn't thinking much more than $250 or so. I wouldn't have to deal with removing the rear axle, altho it'll be harder to do with it still attached. I was hoping to find some steel leafs & a G80 axle to swap in, but I didn't have much free $$ flowing earlier. This month we get our bonus (our financial year is from Sept-Aug), so I get to spend it on this, tires for the wife's van, and maybe a few other goodies, the rest I save for Christmas gifts. I'm not 100% sure on my actual after tax amount, but it'll be nice after a two year drought.

NotJim (workinVan), yup, that cl ad is what I saw. I actually saw a similar ad from them last year, before I got the van, and saved the old ad because it had a phone # and I thought it might be a source. So when I saw the same ad, I thought I better get on with it. I figure I need some sort of limited-slip for winter. I got the van in March, so I missed most of the bad weather last year.

Hard, maybe if this would be an off-road rig, but my wife gets pissed at my driving already, I don't need to be squealing round corners to set her off too. So no solid diffs allowed.

I wasn't sure if this or maybe a locker would be better, it's just that this is nearby and can be in my hand fast. I was just wondering if it was a good price, and that it could be done with tools the average guy has in their garage.

-Andrew
 
#7 ·
Well here is a different approach to your problem, Just get studded tires, they are really amazing. I know some are going to disagree, but I believe that with studs, you won't be missing much over the gov bomb rear end. It actually only comes into effect under twenty and only if one wheel is spinning. Besides milwakee is pretty flat.
 
#8 ·
Yup, I think you would be wiser to spend the 200 on some really good studded snow tires, and about 100pounds of sandbags over the rear axle.
G-80 AKA "Grenade-80" are only locked @ UNDER 100 RPMS (Wheel Speed) and if you end up spinning out in a snowbank, chances are that you will simply grenade the G80, before you get out of the snow bank.
Now if your ride was AWD or 4WD, the pulling front axle will help the Grenade 80 not spin to much, and help it maintain it's structural integrity. I had a 2wd W/G80, in snow cuz I thought it would help, but it just broke!
:2: :2: My 4 cents worth....
 
#10 ·
local milwaukee CL ad i didn't expect anybody to understand that other then the OP and the other skansin locals perhaps

studded tires are illegal here in wisconsin, we have enough road repair happening around here when it isn't winter as it is.

without hesitation i would buy it

i have practically the same one in my truck and did it myself thanksgiving day last year

yes you can use basic tools to do it in your garage
its easier to leave the axle attached when replacing the diff

and its easy to break parts when you drive like a dork

2 cases of beer and it'd be done...one to drink during and another case for after.

p.s. MilwaUkee has more hills then you think
 
#11 ·
workinVan said:
and its easy to break parts when you drive like a dork
I totally agree, but that doesn't mean you have to do that to break a G80 in the snow.
Dont get me wrong, I have a couple other G80,s in my astro herd too, and they work good, but I still think they have their issues.

Weight over the rear axle and Good Snow Tires is the biggest help I believe, no matter what the diff style.
 
#13 ·
I had the G80 in the '90 Safari and it was great for taking off, but other then that it was still very un-predictable. Once I got the snow tires out back it was awesome all the way around. Wish I would have kept those snow tires my '93 with open diff could use them this winter. Spend your money on some snow tires for the back might be able to find some cheap on craigslist like I did. :shrug:

Welding the rear spider gears together will send you into the ditch on corners like Turf was saying.....crazy ********! :lol:
 
#16 ·
Snow tires brand new are about $125....then if you got some extra rims to put them on your set. $250 for two tires would definatly make the most difference. I just searched all of the craigslist in our area man and no good deals on any snow tires out there. I have failed you! :(
 
#17 ·
#20 ·
So Mr_B, do I owe you a finders fee? :rolling: Yup, saw those $40 tires too. I have a set of steelies waiting to go on that have 235/75 R15 LT and are kinda aggressive. I might replace the two that are a little more worn with a new set of snow tires. Since the last RWD I had was a S10, and it did the one-wheel spin even with a few bags of sand (no snow tires), I thought that the posi might help. I WILL have snow tires, I'm not trying to do it w/o. As workinVan said, there are hills in Milwaukee, I have 2 on my way to work that I've seen people in RWD's get stuck and wind up coming back down. And studded tires are a no-go here.

doyoulikeithere, is an open diff the best, even if I drop in a V-8? Or some sort of locker over the posi? I've only owned open diff RWD cars and I always thought that the Posi was better. I've heard about the gernade G80, but is that only because our diff is inherently weak? I just want to know more.

So general consensus is--Snow Tires & weight over axle > Posi

Thanks, Andrew

p.s. Nick, I'll pass on the chrome rims. Chrome is for Harleys. My van will be flat black & red.
 
#23 ·
is it the stock rearend in the truck still?
cuz think about which is more likely to fail under normal conditions a brand new g80 or stock open diff with 200k of wear and tear

while its amazing what a new set of tires can do to the ride and handling to these vans(thanks bowtie) having some sort of locking diff when needed can make a world of difference. especially when its the warm time of yea and snow tires are not on your van anymore
 
#24 ·
I went from a open diff to a limited slip in the Vic and it was a huge difference in the rain and starting out in the snow, but otherwise I felt no difference. But, ya if you got hills to climb a limited slip would really help especially if you end up having to crawl up that hill. If you can do the work yourself it would be cheap enough. I personally wouldn't do a rear carrier swap myself I paid the $300 in labor to have the rear end professionally rebuilt and new limited slip carrier installed in the Vic. :2:

Andrew I have seen a ton of Harleys with Red and Black paint and no chrome.... :lol:
 
#25 ·
workinVan said:
is it the stock rearend in the truck still?
cuz think about which is more likely to fail under normal conditions a brand new g80 or stock open diff with 200k of wear and tear

while its amazing what a new set of tires can do to the ride and handling to these vans(thanks bowtie) having some sort of locking diff when needed can make a world of difference. especially when its the warm time of year and snow tires are not on your van anymore
Yes, that's also what I'm thinking. This morning with a little rain on the street, I have to make sure to not hit it so hard so I don't just sit & spin. I park year round on the street, so in winter, I usually dig my vehicle out so I don't have to gun it back & forth, I just pull out nice & easy. I'm more concerned once I'm on the street, where at the top of a rise is a stoplight, RED of course, and that's where RWD's weakness is exposed.

Mr_Bowtie said:
If you can do the work yourself it would be cheap enough. I personally wouldn't do a rear carrier swap myself I paid the $300 in labor to have the rear end professionally rebuilt and new limited slip carrier installed in the Vic.
I've done quite a bit of wrenching cause I'm a cheap b*****d, and I don't see why this isn't one of those things that can be done. Now if I needed some specialized equipment or expensive gadget, then maybe I'd take it in. About the only time my vehicles see a dealership is if I can only get the part there. I figure I can screw up my vehicle cheaper than they can. And it expands my knowledge, and knowledge is power.

Mr_Bowtie said:
Andrew I have seen a ton of Harleys with Red and Black paint and no chrome.... :lol:
Yeah, the COOL ones!!!

-Andrew
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top