Is Bouncing Normal?

[gman72]

I'm probably the only one going back to XREAS after ditching it per the many threads I read on this forum claiming other setups are "so much better."

I just dropped ~$1100 in all the XREAS replacement parts (all 4 shocks + center control units + lines), and will be doing the swapout of my Bilstein 5100 setup to go back to XREAS tomorrow. I'm simply OVER the excessive body roll and nose dives with any other setup, especially for the type of driving I do.

In addition, I do heavy towing, so that's probably what helped blow my XREAS shocks in the first place, hence adding airbags when I replace them this round.

If you have XREAS and only a component or two need to be replaced, it can be done with minimal expense...the usual failure from my experience is the shock itself (again, my experience is heavy towing which probably stressed them a lot). Since the front right, back left are linked, if you only got one bad component (typically one absorber), you can replace if done correctly via the check valves and be fine.

Think twice before ditching this system just because what you read and what others (most who've never driven an XREAS setup b4) tell you. I'm so getting tired of reading these threads where people comment "just ditch the system alltogether" ...nonsense. It's simply a superior system than any of the aftermarket ideas IMO. True the Bilsteins get you that leveling in the front, but you can accomplish that with XREAS and a spacer. And if you're rock crawling, then fine I agree, go with something else. But no way no how does anything out there W/O the crosslink XREAS get rid of the body roll and nose dive that XREAS does, especially for us that probably drive 90% on the highway.

---> XREAS driver for 8 years b4 switching to Bilsteins and now switching back. Wish I would have just spent the $500 or so more when replacing with Bilsteins last year instead of trying to save a few bucks.

 

[gman72]

Going back to the OP, depends on what sort of 'bounce' you're experiencing. My 5,000lb boat was very heavy on the tongue, and with XREAS it is pushing the rear shocks down a lot, but since cross linked the front shocks try to compensate, hence giving a sense of bouncing / truck trying to level itself, exactly as the system is designed.

If you already have factory airbags you should make sure they're inflated fully when towing with XREAS. No idea what my tongue weight is but it's been definitely heavy enough to weigh the rear end down dramatically, hence why I was using something like this (upside down) Ball Mount 2-3/4" Rise or 4" Drop, 6,000 lbs Draw-Tite Ball Mounts 2753, to compensate, yet still had the 'bounce' effect where the XREAS suspension was trying to level things out:

Inspect your shocks ... see any leakage? Oil spots? But please don't ditch a $2500 system from the factory before getting all the facts straight. Been there. Done that. Mistake.

 

[gman72]

XREAS is a closed-circuit system; thus, you cannot replace just one shock. You also need to replace the other shock that it is connected to.

Correction ... you CAN replace just one shock - total myth. There is a check valve where the shocks connect to the lines / center controller, and if only one shock is bad you can replace just that one, no problem. In fact, even the new setup I have from the dealer splits the front lines into two parts with an additional check valve (probably to ease complications in shipping vs. the OEM one big huge L sized pipe). It's not an ultra high pressure system or anything, just pre-oil filled.

The problem comes in where you're replacing multiple components, at that point it's considered too much has 'leaked' from the system to compromise it, hence the recommendation to replace all connected parts. But even per the Toyota service manual, replacing just one absorber is not a problem.

 

[JB.]

gman72,

Thanks for posting. Interesting stuff.

 

[JimKW]

Thanks for the info Gman72. I had not intention of ditiching the xreas system without taking it to the dealer, I guess, to have it checked out. I get the bounce when I'm NOT towing. When towing it rides fine and I'm towing about 3600 lbs.

This thread has been very helpful though in letting me know I can NOT just change my shocks like I have on other cars. Has anybody found any diy information on changing the shocks yourself when you have xreas? I've searched a little but have found nothing yet.

 

[gman72]

Has anybody found any diy information on changing the shocks yourself when you have xreas? I've searched a little but have found nothing yet.

Yes, I have everything on it. PM me with your email address and I'll send you all the XREAS pages from the Factory Service Manual...

Also if you have an AllData subscription they have everything in there as well: ALLDATAdiy.com :: Leading Source of Diagnostic and Repair Information

There are a couple MAIN POINTS if every diy'ing XREAS (or for that matter any mechanic working on it, since highly likely that if they're not a Toyota dealer they won't know anything whatsoever about this system):

1) you must disconnect/reconnect at the appropriate joints, otherwise you compromise the system. 2) You must work on it with the vehicle suspended via jackstands on frame or a lift ... cannot have pressure on the suspension or any wheels on the ground (e.g. cannot jack up the front, replace, then go work on the back, since the fronts are x-linked to the rears and you have to have the pressure off both front and back @ the same time).

Here's what it looks like off the truck (I just took this off this AM).

As prior posters mentioned, you need to check all the lines/joints, and each shock absorber for leaks. Since you bought the truck used, it's always a possibility that somebody in the past unhooked the system wrong, which would've bled the system out. But it definitely should not be bouncing or 'riding like a truck.' w/o any other mods.

 

[JimKW]

Now I'm really confused.

I had the boat hooked up to the truck all weekend because I was sealing the driveway. I took the boat out Sunday and the 4Runner towed fine. I put the boat in the garage last night and then went for a ride in the 4Runner. It bounced going down the driveway and it's got a slope buy fairly smooth. I went to Kroger and it bounced like crazy just going across the parking lot. I thought something was really wrong cause it seemed to bounce more than every before.

I made an appointment to take it to the dealer tomorrow morning (Wed) just to have it checked out. This morning I debated whether to drive it to work or not because of the way it felt last night.

I decided what the heck and took it. Didn't notice any bounce at all going down the driveway and it rode perfect the entire 30 miles to work. No bouncing whatsoever. You could not want a truck to ride any better than it did this morning.

What the heck is going on?

 

[colombo]

Do you have an air suspention by chance?

 

[JimKW]

yes I have rear air suspension. I have no idea if I need to do something to use it though. I also have that feature that raises and lowers the vehicle. I lower it when I am hooking up the boat and raise it back to normal for driving. Never really had it in the H position. When I try to drive with it in L it goes to N on it's own.

 

[colombo]

)))))))))))))
This is it)))))
Nothing wrong with your truck. When you put load on the back (boat). Your suspension pumps up to level your truck. When you unhook your boat with motor off, your truck's back is still pumped up thus giving you bouncy filling. You need to level it back to nutral position yourself (can do it only when motor running) or when your speed goes higher then 40 km/h, it will level itself automatically.

 

[JimKW]

It bounced for quite some time and on open highways going much faster than 40 mph. Last night I did reset it to the N position before leaving. I think there might be something wrong with the system not sensing something right maybe. Up until this morning it has been bouncing quite a bit at highway speeds, but it did not this morning. I might have scared it by telling it I'm taking you to the dealer.

After I got out of it last night I did walk around it and manually bounce it by pushing it up and down trying to get it to bounce while sitting still in the garage. I'm thinking maybe some kind of sensor was stuck or something. At least I know now it will ride fine and does not really need shocks.

Still going to have it looked at tomorrow at the dealer. They said there would be no charge to have them just look at it.

 

[colombo]

I see. Let us know what dealer finds out.

 

[JimKW]

When I took it out to lunch today, I was stopped at a light and I felt something while sitting still. The guy with me thought I was letting my foot off the brake and then pushing it, but I wasn't. I think it was trying to level itself or something just sitting on the road in traffic. You could here and feel a slight thumping like somebody was hitting the back of the car. Hard to explain.

 

[ARK_SWAMP_RIDER]

Sounds to me like the rear air setup is malfunctioning. I would bet that its sticking in the high position (even though the dash indicator shows normal). This is fiarly common, especially where the salt the roads in the winter. Imo I wouldn't pay the dealer to look at it. From what I've seen, its nothing but a wild goose chase that ends up costing way more than it'll work. Ill post a few links when I can, I'm posting from my phone now. I remember someone took the sensors off and cleaned them, seemed to help

 

[ARK_SWAMP_RIDER]

Here's you some reading on the issue and conversion info:
Stock Rear Ai\rbag Problem - Toyota 120 Platforms Forum
Auto leveling problem - Toyota 120 Platforms Forum
Rear Air Suspension Problems? Options! - Toyota 120 Platforms Forum
Ditching the Air Suspension. Ideas? - Toyota 120 Platforms Forum
GX470 Overland 2.0 conversion - Toyota 120 Platforms Forum

 

[gman72]

Sounds like the rear air suspension is acting up for your bouncing issue ... maybe bad sensor or something? I'd imagine that it would be more bouncy with higher air pressure in the rear air, but from what I understand the factory system is supposed to level it out after xx mph.

But that 'thump' while stopped that you noticed could have simply been the slip yoke, typical issue with this model. Search thump or clunk in the forums, you should find some threads on that ... maybe grease up the slip yoke and driveshaft to get rid of that, but it should be totally unrelated to any bouncing issue I'd think.

 

[ARK_SWAMP_RIDER]

Sounds like the rear air suspension is acting up for your bouncing issue ... maybe bad sensor or something? I'd imagine that it would be more bouncy with higher air pressure in the rear air, but from what I understand the factory system is supposed to level it out after xx mph.

But that 'thump' while stopped that you noticed could have simply been the slip yoke, typical issue with this model. Search thump or clunk in the forums, you should find some threads on that ... maybe grease up the slip yoke and driveshaft to get rid of that, but it should be totally unrelated to any bouncing issue I'd think.

The factory system is suppose to go back to the normal position after so many mph (somewhere less than 10 I believe). Problem is that the sensors get corroded and it gets stuck in the high position. The more air that's in the bags, the more firm your ride is. It's just like putting a set of lift coils like OME that are designed for those with a few hundred pounds of added weight on a stock rig. It'll bounce like crazy unloaded, but when loaded down the ride is pretty good.

What I would advise doing is when you notice it bouncing, stop (leave the 4runner running) and measure the distance from the fender to the ground. This will tell us if it's staying in the right position.

 

[JimKW]

I'm at work now so I don't have time to look at the links you posted, but thanks and I will look at them later.

I just got back from the dealer and everything looks fine. No leaking anywhere and could not see any obvious corrosion on the sensors. It was not bouncing at all when I took it in, but based on what I told them they recalibrated the rear air. Now it's bouncing again.

I was just going to turn around and go back, but I think they might say I am just being too sensitive which I do not think is the case. But I definitely feel a difference in the ride from what I felt yesterday and on the way to the dealer this morning.

The mechanic looked at it for over an hour, test drove it and let me look up under it also and they did not charge me a anything. Got a feeling this will end up being one of those things you just have to live with.

 

[ARK_SWAMP_RIDER]

The main suggestion I can make is to measure the height with the vehicle running when you notice its riding rough and when it is riding smooth. My guess is its sitting higher when the ride is rough. Also, in one of those links, someone manually let air out of the bags and then pulled the fuse to keep it from raising back up. This was a temp fix that improved the ride for him.

 

[JimKW]

So I get in it to come home from work tonight and after I start it, I move the Height Adjustment to the H position. I look in the mirror and can see the car is going up. I put in in the N position, then the L position, then back to N and turn it OFF. Truck didn't bounce at all on the way home.