2010 LX570 - Spring upgrades Fr & Rr (10 Viewers)

[gryphen]

Okay I have been reading endless threads with regard to different LX570 setups and testing etc, but somewhere in all that reading I get lost when it comes to what is the consensus on what are the best Spring changes to make to improve offroad and towing performance.

I am seeking advice (as a non-mechanic)(newb) with regards to the best springs to maintain a reasonable driving experience, not impacting unnecessarily the AHC, and something that either maintains ride height or provides a reasonable increase in height, whilst still providing an increase in load carrying (Cargo/accessories + Hitch weight) up to the max axle load limits.

I'm in Australia, so some of the restrictions placed upon me being road legal might differ from those people overseas.

I did see one series of posts that mentioned the Terrain Tamer springs (TTCS 2168) for the rear, but I have not seen something along similar lines for the front springs.

Any advice much appreciated, I look forward to the replies.

Thanks in advance.

 

[grinchy]

There is no off the shelf front spring. A couple years ago a member did measure the front spring constant (I’ve forgotten it now), and an Eibach part number that might work (or might not), along with maybe new perches fabbed was found that was a bit taller.

I’d have to go look around, if you’re searching I was the one looking in the Eibach catalog.

It was during a gym meet, so probably January thru April.

 

[grinchy]

From the long travel thread

If you commission a shock collar like Westcott uses but with a flat bottom and the inner diameter matched to 3.75” and a 1” ‘drop’/longer you can put a 20” 3.75” (2” lift) off the shelf shock in there. I think we decided <in the lx570 spring thread> to target mid 300s in/lb spring constant. Stock spring was 17.6” long.

Eibach id 2000.375.0350S
Length inches.inner diameter. Spring rate

 

[TeCKis300]

Okay I have been reading endless threads with regard to different LX570 setups and testing etc, but somewhere in all that reading I get lost when it comes to what is the consensus on what are the best Spring changes to make to improve offroad and towing performance.

I am seeking advice (as a non-mechanic)(newb) with regards to the best springs to maintain a reasonable driving experience, not impacting unnecessarily the AHC, and something that either maintains ride height or provides a reasonable increase in height, whilst still providing an increase in load carrying (Cargo/accessories + Hitch weight) up to the max axle load limits.

I'm in Australia, so some of the restrictions placed upon me being road legal might differ from those people overseas.

I did see one series of posts that mentioned the Terrain Tamer springs (TTCS 2168) for the rear, but I have not seen something along similar lines for the front springs.

Any advice much appreciated, I look forward to the replies.

Thanks in advance.

Upgrading AHC should be approached with a different philosophy from static suspensions. Stock, it already has a strong ability to compensate with spring rate and damping, to handle pretty heavy loads. Perhaps some of the upgrading is really about preserving that built in capability and not diminish it.

One of the common fallacies to off-road performance is to increase spring rates. Actually, the most supple spring rate, while still being able to handle the load along with increased damping, and keeping things off the bump stops, is where real performance is. Which is why you see many off-road specials like TRD Pros and Raptors often having less payload than the standard trims. In a long travel setup, more tender spring rates also help to keep some measure of load support on the droop end. Where a stiff spring rate will more quickly fall off.

I have a lightweight build, and I'm setup to handle payloads to max axle limits and beyond. I run the stock springs.

Tuning AHC requires a wholistic approach. So it maybe useful to talk specifically about how much more weight you're installing. And potentially how much AHC lift, i.e. sensor lift, you're looking to run

Most of the tuning tools for AHC involve spacers. Coilover spacers in front and spring spacers in the rear. To preload the coil springs, and preserve hydraulic pressure headroom, to handle overlanding loads.

Here's a few threads which digs deeper on a few relavent topics

LX570 Augmenting for Load

I added a 10mm spacer to each spring at the rear axle. Intent is to add a bit more support to the AHC system, as I tow a heavy 27' Airstream travel trailer. This exact same mod could be done to an LC too, but will result in lifting ~1/2". While the LX570 never asked for it, this is a well...

forum.ih8mud.com

Long Travel AHC

thats a great way to go about this. the ahc line is incredibly stiff and sits so close to the top of the bucket. I highly doubt you would be able to get the whole coil over to drop down low enough and slide over the studs. You would also need to disconnect the sway bar and probably loosen your...

forum.ih8mud.com

Adding Airbags to AHC

@TeCKis300 i drilled out the existing holes to 3/4” using a step bit, but just realized that the air valves don’t line up perfectly. Did you do anything to center the holes or everything will sort out once I lower the rig and air up the bags? Also, do you have any pics of your air lines? I’m...

forum.ih8mud.com

 

[gryphen]

Thanks for the responses, seems I have more reading to do…

 

[grinchy]

The internet says the gvwr of my 2009 is around 7400lb. I’ve added easily 600lb of mass, so 43% of the GVWR to 6000lb empty mass capacity of 1400lb, or an 8% increase to GVWR needed (8000lb). , or a 10% increase in empty mass to 6600., AHC was good with skids and rear bumper (and dynamic load of 35s) (roughly 450 lbs) but lost its ability for dynamics control when I added the front bumper / winch of 150lb). Could be the total mass, or the mass location out front, but that’s when overall dynamic damping was no longer adequate.

Since we can’t change the performance envelope of AHC, we’re left with spring based options - spring rate, preload, or both.

My approach would be to attempt to restore the full 1400lb of dynamic AHC envelope, so I need the springs to be responsible for the additional 600lb of mass. Not just at rest, but also dynamically.

I don’t have it built, and don’t know the proportions of 600lb to assign to each, but I’m imaging a solution which includes preload and spring rate increases, either with spacers and rubbers (existing tech) or spacers and springs (new tech). Longer springs might also be part of the solution, Ideally claiming any long travel advantages along the way