Adding weight to stock AHC

[ohernia24]

Forgive me for probably beating a dead horse here with this post, but I plan on giving my 06 LX a few new parts for looks and functionality when cruising some moderate trails.
- Adding 240lbs total: front bumper (100 lbs), sliders (120lbs), and skid plate (20 lbs)
- Removing about 100lbs: stock front bumper assembly (40lbs-ish?), stock running boards (30-40lbs), and also did some exhaust work so stock muffler and resonator are gone with a new Flowmaster in lieu of those (30-40lbs).

Netting only 140 more pounds.

I plan to flush the AHC fluid for new, as well as get tech stream and get my pressures within desired ranges after everything is added. I’ve seen the posts on how to properly do that.

My question is: If I’m hauling 4 guys with camping/hunting gear around with the new parts listed I’m around 1000lbs (I can’t find a definitive answer on gross weight for stock AHC I know it’s about 1000) so should I be concerned if going on forest service roads, etc. in a fully loaded situation?
The AHC is stock @175k and I’ve never had any issues or suspicions that it’s degrading, but just wanted some feedback if I should be concerned, take any other precautions, possibly add new springs, etc. Thank you!!!!

 

[GTV]

Specific part number for those? Or just look up any LC 100 rear springs

I wouldn’t jump straight to LC springs unless you know you are going to add a significant amount of weight.

 

[ohernia24]

I wouldn’t jump straight to LC springs unless you know you are going to add a significant amount of weight.

My thoughts as well, this is all great info to have on hand though in case I do reach those weight limits.

 

[hoser]

My thoughts as well, this is all great info to have on hand though in case I do reach those weight limits.

Screen name checks out.

 

[ohernia24]

Screen name checks out.

true that!

 

[Jack90210]

Specific part number for those? Or just look up any LC 100 rear springs

Non-AHC springs are substantially stiffer than the Kings.
LX470 AHC spring rate = 95 lbs/in
King = 130
LX450 = 150
100 = 170

Info from this post in the thread Updating AHC system

 

[ohernia24]

Non-AHC springs are substantially stiffer than the Kings.
LX470 AHC spring rate = 95 lbs/in
King = 130
LX450 = 150
100 = 170

Info from this post in the thread Updating AHC system

Just went through that thread, that's great to know. Thanks for sending that. Definitely need to get a baseline reading and go from there on if I even need an aftermarket spring

 

[Wilsil]

Specific part number for those? Or just look up any LC 100 rear springs

No specific number, I just got a used set of a non-AHC Landcruiser 100 series. They have been under the car for 9 years now.
With the additional weight on my car, it just works.

 

[ohernia24]

Finally bought a CReader Elite scan tool and was able to check AHC pressures (I can add a link if anyone is interested in the reader). Front was 8.3 and rear was 7.4. That was with a new bumper (check my new profile pic), but no sliders yet. Both a little high. I’ll probably adjust torsion bars once the sliders are on and hopefully get them close to spec. I’d imagine my rear springs are pretty old hence the higher back pressures. I think spacers might be a solid option for me to lower the rear. My accumulator pressure seemed to be right at spec though at 10.5. Will add new pressure readings once I get my rock sliders, those are still a few weeks away.
For normal specs reference

• Front spec: 6.9MPa +/- 0.5
• Rear spec: 5.6-6.7MPa
• Accumulator spec: 10-10.6MPa

 

[Snow Wagon]

Hello ohernia24,
Once you follow the correct procedure and adjust your front torsion bars to get your front pressure to be 6.9 MPa, it may raise your rear pressure a bit.

Note: Correct Procedure is:
- Cross Level Front via Torsion Bars
- Adjust / Turn Torsion Bars to get front to 6.9 MPa
- Read Rear Pressure and Make Educated Decision on How to Address (Which New Springs or Spacers)

30mm Spacers only decrease your rear pressure by around 0.5 MPa.
I doubt that's going to get you into the 5.6 to 6.7 MPa range.
This is most likely because your current AHC springs are old / tired and you've added a little weight.

If I were you, I'd buy new Toyota / Lexus AHC Coil Springs, since you've added very little weight.
There's a few threads with part numbers.
IMO, King Springs are going to be stiffer than you need, so I don't think I'd go that route.

Good luck.
Tom

 

[ohernia24]

Hello ohernia24,
Once you follow the correct procedure and adjust your front torsion bars to get your front pressure to be 6.9 MPa, it may raise your rear pressure a bit.

Note: Correct Procedure is:
- Cross Level Front via Torsion Bars
- Adjust / Turn Torsion Bars to get front to 6.9 MPa
- Read Rear Pressure and Make Educated Decision on How to Address (Which New Springs or Spacers)

30mm Spacers only decrease your rear pressure by around 0.5 MPa.
I doubt that's going to get you into the 5.6 to 6.7 MPa range.
This is most likely because your current AHC springs are old / tired and you've added a little weight.

If I were you, I'd buy new Toyota / Lexus AHC Coil Springs, since you've added very little weight.
There's a few threads with part numbers.
IMO, King Springs are going to be stiffer than you need, so I don't think I'd go that route.

Good luck.
Tom

Thank you Tom! Much appreciated