Static suspension lifts on IFS vehicles make no sense. They make even less sense on AHC, where the suspension is already designed to give you the one benefit of a lift, when you need it, without all of the negative effects the rest of the time.
AHC spacers? Sensor lift? Both?
- Thread starter aaronrules
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Accuracy of the data only occurs when -the wheels are pointed straight, the vehicle is on flat ground, the temp sensor is unplugged at the pump, the vehicle has a full tank of fuel, the vehicle is in neutral height after coming up from low height, and the driver is outside of the vehicle when recording the data. Yesterday @Rvp reported a front pressure of 10.1 so what's the odds this current data is accurate?
Agreed there are some unknowns still and we need more info. That being said, those pressures are pretty much what we expect to see if somebody just raises the sensors 2 inches. And that's a shortcut to AHC failure. Hopefully we get more complete info so we can help @Rvp avoid some frustration.
thanks all, i’ll be back in town this weekend and providing the fender numbers. as fas as cross leveling is concerned i haven’t done that.
i just did the ahc sensor lift where i turned the screws and put them back on.
have a good week yall!
Sounds like you did the easy part of the sensor lift, which is adjusting the sensors to your desired N height. The hard part is getting the suspension to function properly at that height. By adjusting the sensors you have forced the hydraulic component of the system to bear more of the GVW than it was designed for. You have to increase the preload of the mechanical springs (torsion bars and coils) to compensate. That means adjusting, and possibly re-indexing, the front torsion bars and shimming and/or replacing the rear coils to get your neutral pressures in spec.
After measuring from the center of the wheel hubs at normal height i recorded the following numbers
FRONT DRIVER-21”
FRONT PASSENGER-21”
REAR DRIVER-22.5”
REAR PASSENGER 22.5”
was pretty even give or take all around. car hasn’t been driving around it’s been sitting.
FRONT DRIVER-21”
FRONT PASSENGER-21”
REAR DRIVER-22.5”
REAR PASSENGER 22.5”
was pretty even give or take all around. car hasn’t been driving around it’s been sitting.
So you did a sensor lift. Now the hydraulic components have to work overtime to maintain that height and the neutral pressures are way out of spec.
You have a few choices. You can re-index and adjust your torsion bars to get the front pressures back in spec, then see where your rear pressure ends up and add coil spacers, as needed. This would be the best for maintaining ride quality.
Your other option is to install higher rate bars and springs. Some people have used non-AHC OEM bars and coils. The King KTRS-79 rear coils are also a popular choice. However, if you don't have the additional weight to necessitate the higher rate, you will end up with an over sprung suspension with terrible ride quality, regardless of your neutral pressures.
Your best option is to lower your sensor lift to something reasonable. If you still want the benefits of a lift, make up the height with a body lift. You will get the best of both worlds.
If you want a helpful assessment of your current data and recommendations on how to get your AHC within spec, post the techstream data list with the wheels pointed straight, the vehicle on flat ground, the vehicle with a full tank of fuel in neutral height after coming up from low height, and you outside of the vehicle when recording the data. Give one pic of the techstream data with the temp sensor unplugged at the pump & one with it plugged in. Otherwise you are going to get lots of recommendations pulled out of arses from self annointed AHC guru's.
Yeah, you need to do some significant work if you keep the sensors where you have them now. Reindex t bars, maybe new tbars, new rear springs and spacers, diff drop, extended sway bar links, shock extenders, ucas, etc...
Or.... You know... Just undo some of that sensor lift.
yes undoing them a bit would help, i’ll give it another go tomorrow thanks all
On mine if i take the techstream data picture after coming down from High into Neutral i get this 10.2 8.2 10.4 . In Neutral up from low i'm at 6.9 6.9 10.2. The data is only accurate in Neutral after coming up from low. Unless you weigh 600 lbs. and or you cut your front sensors you should be fine just cranking front tb's and lowering the rear sensor a little bit. Make those adjustments in small increments and monitor the changing data in Neutral Height after coming Up from Low height. You'll be fine.
i started the car today and now it stuck in Low , i press Neutral it goes up and comes back down to low. doesn’t have the option for Hi either. i was unable to make any adjustments last weekend so i’m still stuck on this thing.
If your screenshot a few posts up is from L to N, you are WAY over pressure on the front and overpressure on the rear. You would need to turn the T bars approximately 20 turns on each side. It would be unlikely for you to have 20 turns worth of thread available.
We would expect that to be stuck in low.
I would start by reversing the sensor lift in the rear . Crank the front torsion bars a few clockwise turn try to get it back to neutral then get us some tecbstream data.
Slide the rear sensor down an inch or so then crank your front TB's. Start with 3 clockwise turns each side. If that does not get you back up to neutral. More turns on TB will be necessary and possibly more lowering of rear sensor. Once you do get in N height put up the techstream and we can suggest fine tuning from there. You are most likely going to atleast need some rear spacers. Good luck.
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