AHC routine maintenance? (1 Viewer)

[nickswan]

I have been getting an intermittent AHC OFF dash light since the day after I brought it home, and its been coming on more and more until yesterday it went into LOW mode with only my wife kids and myself in it. Thats about 450 pounds of people a full tank of gas and the 3rd row seats in, hardly overweight. A quick measurement of the four corners showed that the driver front was a half inch lower than the front passenger side. I cranked away on the driver side T-bar until it was level with the passenger side, and a quick test drive shows the light is out. Would a half inch difference throw the light? I would really like to keep the AHC as long as financially possible, but refuse to sink more money into it than the price of a new OME heavy kit. Im only getting 8 graduation marks from High to Low, so I assume its close to going out. and I assume after 13 years and 112k miles the stock coils and T-bars are shot.

are any of the aftermarket coils close to the stock AHC LX coils? or are OEM T-bars and coils the only option? what about an airbag helper for the rear and routine cranking of the T-bars?

I've found OEM coils for $96 a piece and torsion bars for $45 a piece, $300 well spent? or am I just delaying the inevitable?

 

[gotmud]

You're more likely to see worn rear coils than front torsion bars. The weight on the front end tends to be more static. The coils are kinda known for being a little on the soft side. I just replaced a set for a customer that had sagged almost two inches.

 

[jOnathN]

Since it has been erroring for a while and you have not fixed it all bets are off as to what is *currently* going on. Could be as easy as a bad sensor. However at 112k and 13yrs the 4 accumulator springs (globes) are getting old and very well may be flat. That's a lot of age for the diaphragms.

How is the ride; harsh, bouncy, comfortable, ??

Re torsion bars and springs: that won't even delay the inevitable. Money wasted IMHO. You'll either need to fix the AHC or replace it.

IMO YMMV, etc.

 

[nickswan]

Well, cranking the bars and leveling the driver and passenger side seems to have extinguished the AHC OFF light. It looks like it just needed to be tightened up, my question was if the half inch difference would set the light off, or if I have bigger problems. The fact that the light hasn't come back on answers that, I guess. It has a noticeable ride difference from sport to comfort, but the 8 graduation mark difference from HI to LOW is what concerns me, is it the pump that's going out or the globes? If I can get a new pump for a few hundred bucks and get another few years out of the system I will, but if it means $1200 in globes im done with it.

 

[PADDO]

How's the AHC fluid? if its tired and dirty I'd change that out. Did mine at about 65k and it improved the ride considerably.


________________
'03 LX470, night vision, HIDs

 

[uHu]

Your globes are probably quite low in pressure after all those years. But, good springs help the globes last longer. At this age you should probably have changed the coils twice, and adjusted the TBs. When the springs weaken over the years (max 5 on avg), the pressure in the globes increase to compensate, which lead to a shorter life.

That you have stopped the light coming on by tightening the one TB is because you have taken a bit more of the weight off the AHC fluid and globes, but you really need to change the coils. Measure the fluid pressure to see that the neutral pressure is withing range. It is for sure to high at the rear, - up front you can adjust it to spec.

 

[nickswan]

I changed the nasty black fluid out a few weeks ago but didn't notice any change. Anyone found a cheap way to check the pressure at the globes or am I stuck paying crazy dealer prices?

 

[uHu]

It's 110 % certain that the pressure at the back goes over specs after max 5 years sitting on those coils.

For checking pressure - find someone with a LSPV gauge kit.

 

[nickswan]

the light came back on so i cranked the other T-bar and now its out again.

if it comes back on ill try some new OEM rear coils since i can get them for $96.

if it comes back on its getting gutted and sold to pay for an OME heavy kit.

 

[jOnathN]

If you need new globes get a quite from Akella on the board. He seems to have the most economical source for the factory parts. Beno or CDan would be the best traditional bet.

J