Astro Van Question: Over Active ABS

[TroySmith80]

Hey I know there are a few astro van experts here so i thought i'd ask...

I have an 03 AWD astro cargo van that i use for work. I drive it every day, all over town. It is ABS equipped and the ABS seems to be pretty aggressive. That is to say, it cuts in quite frequently. It seems to work well when it is needed (it's often snowy around here), but it also cuts in frequently when it seems like it shouldn't be (because i have good traction at that moment).

Usually this takes the form of just a little 'groan' and pedal feedback just as i'm coming to a stop. Not so much that it changes my rate of deceleration, but i definitely notice the sound and the pedal feel. Then, the other day i was coming to a stop on clear pavement, and when i was down to just a walking speed, the ABS cut in rather aggressively and the van almost coasted out into the intersection. I had never had that happen before! It was rather concerning, because if it gets worse, I'll never know when i may effectively have no brakes!

I'm hoping there is something simple I can do (clean a sensor?) to remedy this over-active / over-aggressive ABS problem, without having to spend a bunch of money at a shop.

Any ideas? Anyone ever had a similar problem?

 

[chasespeed]

Both of my mothers Astros did that... it was pretty annoying to be honest.... and every other Astro I did was as well... My S10 was obnoxious.... I disconnected the ABS, after trying to clean the tone rings, and replacing a couple sensors.... my Snap-On ABS diagnostic, said everything was okay... I gave up... it bothered me....

Is that your case? I dont know, and I am NOT telling, nor advising you to do that, not even hinting at it...

Another thing that can throw your ABS into fits... Are all 4 tires the same? Brand, style, size, etc.... AND, are your pressures as recommended?

It acts based on seeing a difference in wheel speed, at any wheel, once that brake light is on..... SO.....

Chase

 

[TroySmith80]

Thanks for the feedback. Good to know mine isn't the only one doing it. You never had any "runaway" problems then?

 

[ihatemybike]

Yep, matching tire size is very important with ABS on these vans. Not doing four tire rotations can even wear originally matching tires to different diameters causing problems.

Another thing to check is the front wheel bearings. If they are going out their erratic movement can cause the ABS to kick in. Came way too close to someone's rear bumper finding that out.

 

[BCHauler]

I had a 1990 Astro that I put a v8 into. It had 4 wheel ABS that sometimes kicked in for no reason. I cleaned off the ABS sensors at the wheels and the problem went away. It's been a long time since I had the wheels off of one so I don't remember the details of the servicing, but it wasn't difficult.

 

[TroySmith80]

Thanks for the tips guys. The van had all new matching tires as of last summer. Might be a good idea to rotate them now and look for sensors to clean while i have the wheels off.

 

[T.Low]

I had a 1990 Astro that I put a v8 into. It had 4 wheel ABS that sometimes kicked in for no reason. I cleaned off the ABS sensors at the wheels and the problem went away. It's been a long time since I had the wheels off of one so I don't remember the details of the servicing, but it wasn't difficult.

A v8 in an Astro must have made Bowen Island seem even smaller!

 

[BCHauler]

A v8 in an Astro must have made Bowen Island seem even smaller!

Haha. I had it before we moved here. Actually, I remember you from astrosafarivans.com . I was canadavan over there. Then I sold my van and moved on to 4x4 pickups.

Must say though, I still REALLY like vans, and Astros are great.

 

[JKIslander]

Check your wheel bearings and the wheel speed sensors. Chevy trucks are pretty famous for doing that.

You can replace the sensors separate from the bearing, but its best to order the matched set. I know you can get them from the dealer, not sure if aftermarkets come as a set.

If you have access to a fancy scanner you can watch the wheel speed data and see which side is acting up, and replace that side. Or just buy one, put it on and if doesnt fix it, swap it to the other side, they are interchangeable.

 

[r_w]

What cured it for me in my Silverado was changing to heavier tires. A little more rotational mass calmed down the system.

It will still twitch if you hit a pothole while braking, but only ONCE--not the lose the rear brakes for the rest of the stop thing. I almost overshot the stopsign into an oncoming semi before I got it fixed!

 

[Loopie]

I guess my ABS works fine??? It's never activated while stopping in snow or ice (not that I've been in a situation where I thought it should have kicked in mind you)...maybe next yr I'll slam on the brakes and see if the ABS actually works! :bike_rider:

 

[TroySmith80]

next year? You run out of snow already? You can try on some gravel, dirt or grass.

 

[Loopie]

We're probably done with snow/ice in town...but you're right, 10min from my door I can be in 2ft of snow/ice:elkgrin: