What kind of 4wd system does a Astro Van have?

[ankarback]

I'm thinking of maybe buying one to use as a daily driver during the winter. I figured that someone here knew if they are a pos or if they work allright. Worst terrain it's going to see is around 1 feet of snow.

/Johan

 

[dremu]

I'm thinking of maybe buying one to use as a daily driver during the winter. I figured that someone here knew if they are a pos or if they work allright. Worst terrain it's going to see is around 1 feet of snow.

/Johan

Pretty sure it's characterised as all-wheel drive, i.e. all four wheels are driven, but no low range. I don't know if there's a center differential or not.

-- A

 

[ryan22re]

Most of them have NP136's or something similar which is about the same thing as an autotrac t-case (NP246's) minus the low range. Use wheel speed sensors to determine how much torque needs to be applied to the front wheels via a clutch pack and a shift motor to engage the clutches.

Some had a viscous coupling that split the power 40/60 or 35/65 or whatever it was. Never have driven one in the snow, but have driven them. Really hard to tell they were there.

Best thing is that a "real" t-case with low range would bolt in, save for some goofy manual shifter or swapping in the t-case controls from an s-10 or a earlier model fullsize for electric shift.

 

[beater_k20]

actually, i've heard of bolting the AWD Astro case into a 4wd S10 (a la Syclone/Typhoon). the chassis of an L/M van is based on that of the S/T series trucks (S10/Sonoma).

 

[ryan22re]

Yeah, I think the viscous coupling ones were earlier models that used bw t-cases. Which would be a direct bolt in deal since they don't require any external controls.

Pretty sure that the newer ones are torque on demand based off of the rear vs. front wheel speed.

 

[supersize75k5]

the kind that can get the front end a foot off the ground!

just work the gas and the brake at speed and enjoy

 

[ankarback]

Thanks for the info guys. No lowrange doesn't matter since I was thinking of using it as a daily driver but I don't like wheelsensors and viscous couplings. That's to many things that can go wrong on old cars.

I think I'm trying to find something with a ordinary TC instead like a S10 or maybe a K5 with the 6.2 Milages does mather since I have a long drive to work every day.

 

[beater_k20]

I don't like wheelsensors and viscous couplings.

dont like viscous couplings? avoid anything with an automatic trans then. there's no mechanical connection between the engine and the rest of the drivetrain, just a viscous coupling.

 

[sled_dog]

Thanks for the info guys. No lowrange doesn't matter since I was thinking of using it as a daily driver but I don't like wheelsensors and viscous couplings. That's to many things that can go wrong on old cars.

I think I'm trying to find something with a ordinary TC instead like a S10 or maybe a K5 with the 6.2 Milages does mather since I have a long drive to work every day.

how old? Wheel speed sensors don't go bad too often. Neither do control modules. They don't have any actual moving parts (use magnetism to function) so their isn't a whole lot to go wrong in them. AWD Astros are nice vehicles IMO. Personally I would put a real T case in for the option of low range, and the ability to just cruise in 2wd.

 

[pvfjr]

I'd go for one, not bad rigs if you ask me.

 

[ankarback]

dont like viscous couplings? avoid anything with an automatic trans then. there's no mechanical connection between the engine and the rest of the drivetrain, just a viscous coupling.

Never thought of a automatic trans like a viscous coupling but you are right, it is. I know a lot of people who drives cherokee and grand cherokee jeeps. The viscous couplings in those TCs always goes bad after some hard use but then again they're jeeps

 

[RootBreaker]

wasnt there a flexy van on one of the TTC videos?

or you could do this..

 

[longbedder]

My mom has driven GMC Safaris (same as an Astro) since 1985. She's on her 3rd one. Numbers 2 and 3 both had/have AWD. She got rid of #2 because it was stolen, trashed, and recovered.

She's never had a problem with the AWD, and the vehicles are very good and reliable in general. #1 we gave away to some family friends who needed a vehicle - that thing is still running strong with the original motor and a rebuilt trans (240,xxx mi).

My folks live in Wisconsin and deal with snow regularly.

 

[u2slow]

Up to at least '98, the Astro/Safari uses full-time AWD - it does not disengage ever. They are a tad thristy on the petrol. If the t-case goes south it is getting VERY hard to find a replacement - rebuilt or used.

The front axle is nearly identical to the S10, only without the actuator, and uses a pinion flange instead of a yoke.

Front suspension is chevy 1/2-ton with unique torsion bars and hubs/rotors.

 

[TheSunDanceKid]

ah the only time ive drivin them is when i used to jump them you get some air on the bitches hit a small tree one time it just blowd over with a small dent and have ramped some pretty good shiot in them so id recommend them

 

[Pookster]

ah the only time ive drivin them is when i used to jump them you get some air on the bitches hit a small tree one time it just blowd over with a small dent and have ramped some pretty good shiot in them so id recommend them

They aint bad at all. ABout as reliable as a s10... which in itself, is uhh... nevermind. I personally dislike the s10 blazer a lot. the s10 pickup is ok. Mechanically the same, but... man, do the s10 blazers rust. The interiors around the early 90's were terrible.

AWD is better than 4wd in snow driving conditions- You can go above 35/40mph (not that you should, but you could with minimal ill effects). It also has the ability to torque bias between the front and rear axles- something 4wd's cant do, because it distributes power 50/50 to the front and rear.

 

[K5dreamer]

perfectly good vans, i drive one at my job hauling wheelchairs and doing housecall repairs with all my tools. ive even driven it up a dirt hill fully loaded at a decent grade and it handled it just fine. havent driven it in the snow yet but it should do just fine.

added benift is if you get the modification itch, that 4.3L V6 is basically a 3/4 350, so all aftermarket parts for a smallblock will fit the sixer. dunno why gm ever got rid of that engine, one of the best six cylenders ever made IMO.

 

[ankarback]

perfectly good vans, i drive one at my job hauling wheelchairs and doing housecall repairs with all my tools. ive even driven it up a dirt hill fully loaded at a decent grade and it handled it just fine. havent driven it in the snow yet but it should do just fine.

added benift is if you get the modification itch, that 4.3L V6 is basically a 3/4 350, so all aftermarket parts for a smallblock will fit the sixer. dunno why gm ever got rid of that engine, one of the best six cylenders ever made IMO.

What kind of gasmilage do you get? I'm trying to decide beetween an AWD Astrovan, S10 Blazer or a K5 with the 6.2.

I wan't the one with the best total economy. I'm trying to calculate with gasmilage, cost of spareparts reliability etc.

/Johan

 

[ryan22re]

dunno why gm ever got rid of that engine, one of the best six cylenders ever made IMO.

You can still get it in fullsize vans and trucks.

They got rid of it because it is a heavy iron pig. The 4200 that replaced it in the utilities is much better than the 4.3. More power, better mileage, is super quiet and lighter to boot. As for the other variants of the 4200 six, I really have no comment (3500/3700 five cyl. and the 2800 4 popper). They just seem a little under powered.


Back on topic, I would guess that the cost of owning a 4.3 vs a 6.2 "could" be about even. Parts for the 4.3 are cheaper, but gets less mileage than the 6.2 whose parts are more expensive.

Personally I'd go with an s-blazer with a 4.3 and 4wd. A two door blazer would probably be the lightest and maybe get the best mileage. Dunno if they were available with 3.73 gears, but that's the one I'd be looking for. Plus it'd have to be either TBI or vortec, with the edge for simplicity to the TBI, which would mean cheaper repair costs. Throw some 30x9.5s on it and call it done.

 

[pvfjr]

My '89 with a 2.8 has 3.73's, don't know if that's just because of the wimpy motor though...