Auto Level Help / Diagnosis....

[Marioski]

Okay guys I just need some insight on how the auto level actually work? When does it supposed to kick on after the rear end is loaded up?

I asked this because I noticed the air compressor assembly was fubar'ed on my 07 Avy LTZ after I purchased it. Was expecting that. I picked up a new assembly and installed it this week. The air compressor runs at power up for about 5 seconds and I think that's it. I sat on the tail gate to compress the rear and looked like a dummy for about 2 minutes and I didn't hear the compressor turn on. I don't know maybe I'm not heavy enough to detect anything.

Now to add something to the mix, I have a RC Level Kit installed in the front but I have read that shouldn't effect it and it should level off anyway. It's not, I have about 1/2 to 3/4 of an inch difference and the rear sits a bit lower.

Any thoughts would be great!

 

[KMeloney]

Now to add something to the mix, I have a RC Level Kit installed in the front but I have read that shouldn't effect it and it should level off anyway. It's not, I have about 1/2 to 3/4 of an inch difference and the rear sits a bit lower.

I don't understand your last paragraph here. What's the difference you mention BETWEEN? Are you talking about differences in front and rear fender gap? Or, are you talking about the difference in height of the rear that the compressor provides, aired up vs. unaired?

I'm not sure if this will answer your questions, but I'd offer the following:

1. Only the rear shocks air up and raise only the rear of the truck.

2. How much the rear airs up appears to depend on the relationship of the rear to the autoride links, and (I THINK, but am not sure) the relationship of the rear to the ground. My truck will air up when I'm parked uphill, for example.

3. The truck seems to need to be running for a minute or two before the compressor kicks on.

4. If your truck aired up, and only for 5 seconds, and then you stood on the bumper, it simply may have not "needed" more air than what was pumped in initially.

5. There may be a problem with your shocks or compressor (although it doesn't sound like it to me).

6. With the kit raising the front, it's possible that the distance needed for the rear to raise is greater than the autoride links (and maybe the shocks) will allow. I can't imagine that the rear would be allowed to be raised too far -- at some point the shocks and other suspension components wouldn't be able to function as they were designed to.

 

[Marioski]

I don't understand your last paragraph here. What's the difference you mention BETWEEN? Are you talking about differences in front and rear fender gap? Or, are you talking about the difference in height of the rear that the compressor provides, aired up vs. unaired?

I'm not sure if this will answer your questions, but I'd offer the following:

1. Only the rear shocks air up and raise only the rear of the truck.

2. How much the rear airs up appears to depend on the relationship of the rear to the autoride links, and (I THINK, but am not sure) the relationship of the rear to the ground. My truck will air up when I'm parked uphill, for example.

3. The truck seems to need to be running for a minute or two before the compressor kicks on.

4. If your truck aired up, and only for 5 seconds, and then you stood on the bumper, it simply may have not "needed" more air than what was pumped in initially.

5. There may be a problem with your shocks or compressor (although it doesn't sound like it to me).

6. With the kit raising the front, it's possible that the distance needed for the rear to raise is greater than the autoride links (and maybe the shocks) will allow. I can't imagine that the rear would be allowed to be raised too far -- at some point the shocks and other suspension components wouldn't be able to function as they were designed to.

To answer your first question, it's ground to fender lip clearance. With the RC Level Kit my front sits at 37 1/4" (ground to fender lip in the center). My rear sits around 36 5/8" inches. That is after the compressor airs up for 5 second. Keep in mind I purchased this vehicle used and I don't know how long the prior compressor has been non functional.

You're right, it may not necessarily be able to go up that high on the automatic settings and this is where it may be max'ed out. So I guess I have a two fold question, can the level kit be higher then the factory rear height as I'm assuming the compressor/auto ride may not be able to compensate for the additional height with the rear air shocks?

(BTW. ,The rear air shocks can go up that high. Monroe makes a great manual kid with an air line and a shraeder valve that you simply plug into the "t" fitting in the compressor and bypass the compressor itself. I ran this for 2 months before pulling the trigger on a new compressor. I had my rear height manually filled to 37.5 inches - ground to fender lip. I just found it annoying to refill it every 3rd or so day).

So if I understand this correctly the Auto Ride self leveling features works like this

1. System is powered up. Runs after 20 seconds for about 5 minutes.

2. If it senses a load in the rear, after a minute or two it should kick on the compressor (while vehicle is running).


Do I have to do anything with the height sensor links, such as make them longer or shorter to adjust for the front 2" level lift kit?

Do the rear heigh sensor's typically go bad on these things and if so would that set off a DTC code?

 

[KMeloney]

Seems to me that my stock height in the rear was higher than yours. I'd say that my rear height was more like your front height is now.

What size spacer did you use in the front (assuming you used a spacer)?

Do you KNOW that you have the factory springs in the rear, and that you have the factory links in the rear? (I ask only because the said you bought the truck used, and if those things were altered, then you might be on a bit of a wild goose chase initially.)

It doesn't sound like you have a leak in your shocks or air system. If you did, it sounds like the compressor would run for a long time, not a short time...

No, you don't have to mess with the front links when you add a front spacer kit. And you'd only have to SHORTEN your rear links if you were to LOWER the truck. I just wonder if you have the factory rear links in there -- and at the factory length...

Otherwise, if you, say, added a 2.5" spacer in the front (which is common), and didn't add a 1" spacer in the rear at the same time (you should, imo), then you run the risk of the front sitting higher. The truck won't try to air up the rear beyond the highest factory ride height -- it'll only try to raise the rear if the rear dips substantially below it. Or so that's my understanding.

 

[Marioski]

Seems to me that my stock height in the rear was higher than yours. I'd say that my rear height was more like your front height is now.

What size spacer did you use in the front (assuming you used a spacer)?

Do you KNOW that you have the factory springs in the rear, and that you have the factory links in the rear? (I ask only because the said you bought the truck used, and if those things were altered, then you might be on a bit of a wild goose chase initially.)

It doesn't sound like you have a leak in your shocks or air system. If you did, it sounds like the compressor would run for a long time, not a short time...

No, you don't have to mess with the front links when you add a front spacer kit. And you'd only have to SHORTEN your rear links if you were to LOWER the truck. I just wonder if you have the factory rear links in there -- and at the factory length...

Otherwise, if you, say, added a 2.5" spacer in the front (which is common), and didn't add a 1" spacer in the rear at the same time (you should, imo), then you run the risk of the front sitting higher. The truck won't try to air up the rear beyond the highest factory ride height -- it'll only try to raise the rear if the rear dips substantially below it. Or so that's my understanding.

Thank You for the response.

I am pretty much positive the truck is not altered as it was a single owner in his late 50's that owned it. The vehicle was bone stock and it great condition.

I have not thought about the rear springs and I will cross reference the part numbers. You may be onto something as they look newer then the rest of the vehicle. Perhaps they were replaced at one point with the wrong ones.

The height sensor links look to be original but looks can be deceiving. I'll look into that as well and maybe disconnect them this weekend and see I manually raise them if the compressor kicks on.

The front only received a 2" spacer (rough country leveling kit) and I figured I would not need a rear coil spacer. But who knows, maybe I do. I ordered a .75 rear spacer and will give that a shot this weekend.

 

[KMeloney]

Keep us posted as to what you find this weekend.

 

[felixgun]

I put in a 2.5 up front and ended up getting the 1.5 rear coil spacer to be leveled all the way around.