Chevy & GMC Vans

I found a 2002 AWD Van near me late yesterday for sale. It had the 4.3L V-6 engine which I've loved for a long time. Aside from that, I realized I didn't know anything about these vans, and started searching.

Google and wikis only take you so far before you realize you need to talk to like-minded individuals to learn the real nuts and bolts. So, here I am.

I like the idea of a 4WD van, I like the engine, and I'm way psyched to learn that there is a 4L60E in these things.

However, the lack of a low range, the IFS and the subframe/uniframe construction bother me.

I use a Cherokee right now for my way-off-the-road adventures, and its armored and has uniframe stiffeners, but it still leaks thanks to flexing, and I'm pushing 230K miles on it now. The engine and trans have both seen better days, and there really isn't enough space for me and my lady to sleep inside. I have a buddy with an Astro Van, with almost 200K miles on it, abusive, non-oil-changed miles, and his big problem has been losing vacuum to his dash vents.

Anyway, my Cherokee is on 30's right now, and its got a NP242, and I love having the AWD available. I also like being able to run in 2WD most of the time, as its my daily driver too.

So, I came here searching for more drivetrain info, hoping to find out what motors/years guys who have these things like, what transmissions there were, how the differentials hold up and more. I just found out that 2002 is gone, but I'm also starting to lean towards the 98 and earlier borg-warner equipped units because the electrical just sounds less daunting. I prefer OBD2 to OBD1, because an OBD2 vehicle is way easier to smog in CA than the earlier ones, and I wanted the multiport 4.3 from the get-go. So from what little I've learned in a day, it looks like I need to start looking for a 96-98 AWD van.

Welcome!

For what you want to do you can look for any AWD van 1996 and newer. You are going to want to switch to a 2 speed t-case anyway so the NV136 t-case being more prone to failure means nothing. Throw in the 4" lift and 31 x 10.5" tires, trim the front bumper and rear pinch weld seam of the front wheel well and trim a little in the front of the rear wheel well and you'll be good to go. The only thing that may disappoint on the highway would be if you got a van with 3.42 gears. It'll be a dog if you have hills around and/or tow anything.

The 4.3L V-6 is basically indestructible as long as you maintain it. The 4L60E MUST have an aux trans cooler installed or you WILL cook the trans while wheeling. The weak points will be the front and rear diffs. You can put a Power trax no-slip locker in the rear and a lock-rite in the front diff, but I don't recommend the front one.

More items you will need are a set of Rock Rails and a healthy skid plate for the engine/trans/t-case as these hang pretty low. There are threads in here showing what I build and I am pretty sure the drawings are here as well so you can head to your local off-road shop for a custom set. The rock rails stiffen the body up some and I never had issues with too much body flex. I never saw any gaps between the body panels as some do report.

LiftedAWDAstro wrote:Welcome!

For what you want to do you can look for any AWD van 1996 and newer. You are going to want to switch to a 2 speed t-case anyway so the NV136 t-case being more prone to failure means nothing. Throw in the 4" lift and 31 x 10.5" tires, trim the front bumper and rear pinch weld seam of the front wheel well and trim a little in the front of the rear wheel well and you'll be good to go. The only thing that may disappoint on the highway would be if you got a van with 3.42 gears. It'll be a dog if you have hills around and/or tow anything.

The 4.3L V-6 is basically indestructible as long as you maintain it. The 4L60E MUST have an aux trans cooler installed or you WILL cook the trans while wheeling. The weak points will be the front and rear diffs. You can put a Power trax no-slip locker in the rear and a lock-rite in the front diff, but I don't recommend the front one.

More items you will need are a set of Rock Rails and a healthy skid plate for the engine/trans/t-case as these hang pretty low. There are threads in here showing what I build and I am pretty sure the drawings are here as well so you can head to your local off-road shop for a custom set. The rock rails stiffen the body up some and I never had issues with too much body flex. I never saw any gaps between the body panels as some do report.

I am well aware of the 4L60/700R4's tendency to self-bake off road. I've had good luck with B&M Supercoolers in the past to solve it.

I thought that the NV136-equipped units would be harder to get to run right after it was in? VSS-trickery, AWD check-engine lights and so forth? I'm in CA, and Smog is a constant headache. I really wanted to find one with under 100K miles on it, so being able to nab a newer one would make the hunt easier, but if I'll be stuck at smog, then its no good.

Thanks for the heads up on the 3.42s. Pulling on past experiance with engines like this and these transmissions I would figure for 30s or 31s I'd need at least 3.73s but likely 4.10s.

I'll look for the stuff you built. I can build myself, so I don't need to argue with any shops about what I want lol. Is 3/16-s construction the norm here too? I'd imagine it would be, what with similar weights. I'd do rock rails and belly skids right away but probably wait until I've mangled the stock bumpers. What about a gas-tank skid? Is it tucked up high enough to not be an issue?

What's WMS to WMS of the rear axle?

Thanks.

over2land wrote:I thought that the NV136-equipped units would be harder to get to run right after it was in? VSS-trickery, AWD check-engine lights and so forth? I'm in CA, and Smog is a constant headache. I really wanted to find one with under 100K miles on it, so being able to nab a newer one would make the hunt easier, but if I'll be stuck at smog, then its no good.

This thread in here is a discussion about the CA smog issues. The VSS in the NP231C is a direct plug-in.

over2land wrote:Thanks for the heads up on the 3.42s. Pulling on past experiance with engines like this and these transmissions I would figure for 30s or 31s I'd need at least 3.73s but likely 4.10s.

4.10's are perfect for 30 - 31" tires. Power is better than stock, acceleration is great and fuel mileage is as good as stock too. You can probably get by with 3.73's if you can find a van with them. Most were equipped with 3.42's.

over2land wrote:I'll look for the stuff you built. I can build myself, so I don't need to argue with any shops about what I want lol. Is 3/16-s construction the norm here too? I'd imagine it would be, what with similar weights. I'd do rock rails and belly skids right away but probably wait until I've mangled the stock bumpers. What about a gas-tank skid? Is it tucked up high enough to not be an issue?

3/16" is what I use and it holds up great. I didn't do a gas tank skid and I did dent the tank buried in mud once. I had a few light scrapes on the plastic shield but none ever cut through. You have to be very conscientious about the location of the tank and where the rocks are.

over2land wrote:What's WMS to WMS of the rear axle?

It is around 66 - 67". It is the same as most full-size trucks.

Welcome to "Our World" over2land, you have just found the most informational StroFari site on the WWW. Whether you are raised or lowered we have all your answers here, and Lifted AWD Astro is the 4 X 4 man ! You need to post up some pic`s of SPB Dean.

Thanks SoCal, where you at?

I'm just north of Santa Clarita.

LiftedAWDAstro wrote:

over2land wrote:I thought that the NV136-equipped units would be harder to get to run right after it was in? VSS-trickery, AWD check-engine lights and so forth? I'm in CA, and Smog is a constant headache. I really wanted to find one with under 100K miles on it, so being able to nab a newer one would make the hunt easier, but if I'll be stuck at smog, then its no good.

This thread in here is a discussion about the CA smog issues. The VSS in the NP231C is a direct plug-in.

LOL, nevermind.

I was quoting to tell you there was no link, but I see the link in the quoted text. Somehow a bracket got in the wrong place when you did that.

Thanks again.

Temple City, LA 5 miles East of Pasadena on the 210 Fwy. Irwindale Speedway is just 3 miles up the street from me. I`m there at the Drags every Thursday Night ....

LiftedAWDAstro wrote:You can put a Power trax no-slip locker in the rear and a lock-rite in the front diff, but I don't recommend the front one.

As I understand it, the lock-rite is a no-no as long as you have AWD, but if you're planning to use it with a selectable transfer case, it should be OK, right? I've been wondering if fitting this to a S-10 front diff housing and a posi-lock would be a good idea too, since it seems like the axle-disconnect should eliminate any weirdness from the lock-rite while you're driving on the street.

Herbie wrote:

LiftedAWDAstro wrote:You can put a Power trax no-slip locker in the rear and a lock-rite in the front diff, but I don't recommend the front one.

As I understand it, the lock-rite is a no-no as long as you have AWD, but if you're planning to use it with a selectable transfer case, it should be OK, right? I've been wondering if fitting this to a S-10 front diff housing and a posi-lock would be a good idea too, since it seems like the axle-disconnect should eliminate any weirdness from the lock-rite while you're driving on the street.

You are 100% correct. Do the front diff mods you said and throw a locker in the rear and you will have TRUE 4x4! You would want to disconnect the front anytime you were turning sharp or it'll bind like crazy. Plus most of the time 3x would be plenty of traction.

SoCalli V8 wrote:Temple City, LA 5 miles East of Pasadena on the 210 Fwy. Irwindale Speedway is just 3 miles up the street from me. I`m there at the Drags every Thursday Night ....

Sweet, what are you racing?