Cracks in Inner Guards

[HIKDJ Lurker Find all posts View Profile Close HIKDJ]

Re: Cracks in Inner Guards

The KDJ 120 is used quite often for rallye-raids in Africa and elsewhere. Also in the famous Dakar (although the recent one was held in South America) there is a good participation of KDJ 120's and they are very successful in the production car class. Needless to say, these vehicles are heavily and professionally prepared, and this is where Toyota Compétion comes into the picture. I believe that this is a strictly french organisation linked to Toyota France. See http://www.toyota.fr/innovation/motorsp ... rally.aspx
I believe that in this framework the reinforcement kit for the guards has been developed, and they have decided to let the outside world also benefit from it. In France, they are available through the more active Toyota dealerships, I don't know abroad. I believe that the part numbers are:
53 731 600 7 0
53 732 600 6 0
53 733 600 4 0
53 734 600 5 0
but the reference to a mailorder address (http://www.axe4.fr/renforts-ailes-kdj120-kdj125.htm) lists them as a kit, with bolts included.
I agree that the kit must somewhat reduce the effectiveness of the crumple zone. But I have decided that, although my trips in the desert are holiday trips rather than rallye-raids, I prefer prevention of possible cracks, rather than the risk of complicated repairs.

[outbackswine Junior Member Find all posts View Profile Close outbackswine]

Re: Cracks in Inner Guards

After reading about these inner guard cracking issues, and how the usual dual battery location and or ARB steel type bullbars are perceived as contributors to this, I am somewhat hesitant to buy a Prado as I want a dual batt setup, but could live with an alloy bar if I had to. I don't know how much better the alternative batt mounting place on the side of the passanger inner guard would be either..

just how many people here actually have experienced the issue on their cars, and what if any off-roading have you done?

I am all but set on a Prado, but if this turned out to be a reasonably common occurrence on vehicles used off-road, I would prob go to a 100s TD, or dare I say it Disco3.

It has me very worried as it would be terribly expensive to fix, or would mean a virtually worthless vehicle on the used market when it's time to sell if unrepaired or showed evidence of having been repaired.

[sleeky Junior Member Find all posts View Profile Close sleeky]

Re: Cracks in Inner Guards

Is there really any evidence at all that bullbars contribute to the cracking problem? I could understand how removing rubber bushes to compress the front end and minimise bullbar movement can stress the body, but a bullbar is attached to the chassis which moves independently of the body but places no stress on the actual structure as far as I can see. Even bottoming out the suspension should only stress the chassis as the bump stops are not attached to the body.

As has been reported previously, even some vehicles without bull bars have cracked inner guards. My own theory is that the body has no rigidity of its own and as it moves about on the rubber mounts it flexes and finally cracks. I can understand how added weight in the engine bay can (but shouldn't) stress the body but not a bullbar.

I am however happy to be shown where I am wrong in my reasoning.

Neil

[outbackswine Junior Member Find all posts View Profile Close outbackswine]

Re: Cracks in Inner Guards

Is there really any evidence at all that bullbars contribute to the cracking problem? I could understand how removing rubber bushes to compress the front end and minimise bullbar movement can stress the body, but a bullbar is attached to the chassis which moves independently of the body but places no stress on the actual structure as far as I can see. Even bottoming out the suspension should only stress the chassis as the bump stops are not attached to the body.

As has been reported previously, even some vehicles without bull bars have cracked inner guards. My own theory is that the body has no rigidity of its own and as it moves about on the rubber mounts it flexes and finally cracks. I can understand how added weight in the engine bay can (but shouldn't) stress the body but not a bullbar.

I am however happy to be shown where I am wrong in my reasoning.

Neil

I have been thinking along the same lines, as the bullbar has no attachment to the body as such.

[FJ Fender Cracks Lurker Find all posts View Profile Close FJ Fender Cracks]

Re: Cracks in Inner Guards

Hey all, I have specifically joined about this problem. We are experiencing the same exact problems on the 2007+ Toyota FJ Cruiser. They share the exact same 120 frame, and are cracking in the same places you guys are reporting. It is happening to COMPLETLY stock off the show room floor FJ's, as well as highly modified ones. I know this is not just a coincidence here that both platforms are having this problem. Here is a 2 year long thread about the issue (warning will take FOREVER to read, but there is LOTS of pic's for you) http://www.fjcruiserforums.com/forum...body-rips.html. Big problem here and Toyota is doing NOTHING at all to fix or even admit that there is a problem. What's your guy's opinion ?

[pickle Lurker Find all posts View Profile Close pickle]

Re: Cracks in Inner Guards

Here is a 2 year long thread about the issue (warning will take FOREVER to read, but there is LOTS of pic's for you) http://www.fjcruiserforums.com/forum...body-rips.html. Big problem here and Toyota is doing NOTHING at all to fix or even admit that there is a problem. What's your guy's opinion ?

Yeah 296 pages worth. Seems a bit like Nissan and the 3.0ltr problem that they know nothing about.
Dave

[pradomod Lurker Find all posts View Profile Close pradomod]

Re: Cracks in Inner Guards

I have had similar problems with my Prado (2003 5 door 4ltr V6 with Heavy duty OME front and Med duty OME on the rear)). I do a lot of desert driving here in Oman and have since discovered that the buckling and cracking problems much reported on this website are quite common out here too with both Prado's and FJ's, although i get the impression it's more commonly caused by jumps and bumps rather than rutted roads. Toyota know it's a big problem but keep very quiet about it.

The first time it happened to me was last Novemebr when I had a steel front bumper fitted (ARB lookalike but only 60kg in weight). I hit a bump too fast and the the wheel arch & inner wing panels buckled both sides of the car and the front spar on the driver's side also twisted leaving the whole front assembly twisted to such a degree that he plastic engine cover was pressed agaianst the radiator cowl. I was advised by a local rally driver that the Prado chassis is too weak for a steel bumper...the locals know their 4x4's well out here. This particular incident also caused a crack to appear in the lip of the inner wheel arch just above the top of the suspension mounting. The general consensus was that the extra weight of the steel bumper caused the front to "whip" to such a degree that the panels just distorted. It took a month to fix and was an insurance job. The local Toyota dealership did a thorough job and had to lift the body off the chassis to realign it. They reinforced the cracked areas by welding a narrow steel strip about 4" long in each location....one per each wing.

I have since removed the steel bumper and replaced it with the OEM plastic bumper. The front now has about 3" of lift at the front which is great for clearance in the dunes and the car definately feels lighter. However, I recently (inadvertantly) hit another bump at speed and this time the inner wing panel on the drivers side has buckled, albeit to a much lesser degree than before. The gap between the outer wing panels and the front doors has closed slightly as a result but the bonnet alignment looks ok. No cracking anywhere this time around but its a right bloody pain to say the least. It's interesting to note that the damage in both cases has been worse on the drivers side. Possibly due to most energy being caused by the added weight of the driver (....no...I only weigh 10 stone!)

It's reached the stage where I'm considering buying an old jeep or a 90 series Prado as at least they don't suffer from this sort of problem. However, having just seen the link to the french website and the strengthening kits, I'll probably give this a try first. Has anyone actually tried these kits and can advise whether they solve the problem? My immediate thoughts are that they stiffen up the front panels which may cause "bump" energy to dissipate further back...ie result in cracking to even more expensive to repair, front bulkhead. Any thoughts most welcomed.

[ookami Member Find all posts View Profile Close ookami]

Re: Cracks in Inner Guards

After hearing stories about this I did some research and i don;t think this is caused by fitting bars or suspension (correctly matched to the load) as going by the FJ cruiser guys fitting a bar with suspension actually helps prevent the situation. Also apprently according to the FJ cruiser forum in May 2008 Toyota changed their design of the 120 series platforms inner guard design to incorporate a stronger design and so far people have not had problems since going to this design. If you ever have a spare moment and can sift through the anger and frustration that 300 page thread on the issue does have some interesting trends on what can potentionally cause this issue. Basic resolution based on the FJ cruiser forum is to update ur inner guards to the latest design or do some other form of reforcing.

[pradomod Lurker Find all posts View Profile Close pradomod]

Re: Cracks in Inner Guards

Thanks for your thoughts. Looks like I've got a choice. Either use the reinforcing kit sold by Axe 4x4 ...see earlier in this thread ...if i can get hold of it out here (Sultanate of Oman...no 4x4 outlets worth talking about), or take it the a local body shop and have the panels strengthened...not so easy without the expertise....toyota have the expertise but won't strengthen the panels as it will affect the crumple zone performance!! By the way, my car is a 2003 Prado 120, not the FJ and I haven't heard of any simple fixes being carried out by toyota on these...Has anyone?...I'd love to know.

[Guest Close Guest]

Re: Cracks in Inner Guards

I have had similar problems with my Prado (2003 5 door 4ltr V6 with Heavy duty OME front and Med duty OME on the rear)). I do a lot of desert driving here in Oman and have since discovered that the buckling and cracking problems much reported on this website are quite common out here too with both Prado's and FJ's, although i get the impression it's more commonly caused by jumps and bumps rather than rutted roads. Toyota know it's a big problem but keep very quiet about it.

The first time it happened to me was last Novemebr when I had a steel front bumper fitted (ARB lookalike but only 60kg in weight). I hit a bump too fast and the the wheel arch & inner wing panels buckled both sides of the car and the front spar on the driver's side also twisted leaving the whole front assembly twisted to such a degree that he plastic engine cover was pressed agaianst the radiator cowl. I was advised by a local rally driver that the Prado chassis is too weak for a steel bumper...the locals know their 4x4's well out here. This particular incident also caused a crack to appear in the lip of the inner wheel arch just above the top of the suspension mounting. The general consensus was that the extra weight of the steel bumper caused the front to "whip" to such a degree that the panels just distorted. It took a month to fix and was an insurance job. The local Toyota dealership did a thorough job and had to lift the body off the chassis to realign it. They reinforced the cracked areas by welding a narrow steel strip about 4" long in each location....one per each wing.

I have since removed the steel bumper and replaced it with the OEM plastic bumper. The front now has about 3" of lift at the front which is great for clearance in the dunes and the car definately feels lighter. However, I recently (inadvertantly) hit another bump at speed and this time the inner wing panel on the drivers side has buckled, albeit to a much lesser degree than before. The gap between the outer wing panels and the front doors has closed slightly as a result but the bonnet alignment looks ok. No cracking anywhere this time around but its a right bloody pain to say the least. It's interesting to note that the damage in both cases has been worse on the drivers side. Possibly due to most energy being caused by the added weight of the driver (....no...I only weigh 10 stone!)

It's reached the stage where I'm considering buying an old jeep or a 90 series Prado as at least they don't suffer from this sort of problem. However, having just seen the link to the french website and the strengthening kits, I'll probably give this a try first. Has anyone actually tried these kits and can advise whether they solve the problem? My immediate thoughts are that they stiffen up the front panels which may cause "bump" energy to dissipate further back...ie result in cracking to even more expensive to repair, front bulkhead. Any thoughts most welcomed.

I would be hazarding a guess your cracks are more from the stress of impacting dunes, not the normal stress fractures from Bars/batteries.

[Guest Close Guest]

Re: Cracks in Inner Guards

I still dont think it is a huge issue here in Australia anymore.

I dont know of anyone who has experienced it recently, and the fact there are only a "couple" reports on it here, tends to point in the direction I am thinking.

[Golly Advanced Member Find all posts View Profile Close Golly]

Re: Cracks in Inner Guards

I have heard a bit from here and there. Correct me if I am wrong. The 120 body rides on mounts on the chassis, correct. This explains bullbar shakes when the bullbar is not shaking the actual car is. Why would bullbars even come into the equation then, as they are not weighing down the body of the vehicle to stress the guards out. The bullbars are mounted to the chassis. And if dual batteries cause cracking on front guards then Toyota built a week as crap 4x4. I think cracks may be from driving styles more than simply adding weight to the vehicle in my opinion. 30kg of Battery and tray cannot surely crack up a wheel arch. Maybe aftermarket suspension may play a part in cracks and yes, tackling rutts at hazardous speeds may twist the girl into a frenzy and brake her up.... Dunno, just my thoughts. 8) Maybe the body mounts need addressing.

[photoprado Avid PP Poster! Find all posts View Profile Close photoprado]

Re: Cracks in Inner Guards

Golly,

Like anything made with metal and stressed, there is more to this than meets the eye.

That bullbar is sitting at the extremity of the chassis and giving it a shake in the process. Be a brave designer who can predict what will be attached to a 4WD vehicle and how it might be driven, and where it might go. I think the Toyo designers are pretty good, but it looks like they got caught out in the early 120's. I'm kinda hoping that TP is right though, and the problems are behind us.

Michael

[outbackswine Junior Member Find all posts View Profile Close outbackswine]

Re: Cracks in Inner Guards

I think that whilst most people get the concept that a heavy front bullbar is mounted directly to the chassis, and the body is mounted to independantly of that bullbar, we must remember that the additional weight of front bar, when moving about due to bumps and corrugations will be helping the flex the ladder frame more than what would be the case if the bull bar was not fitted.

It makes sense to me that this additional weight could very well be causing the chassis to flex if you like in a downward motion toward the ground, and in turn pulling the chassis down would have to result in pulling the body down to some degree at the points where the body mounts to the chassis, this could well induce cracks in the body and inner guards.

Has anyone loosened up the mounting bolts where the body mounts to the chassis forward of the firewall?

[Golly Advanced Member Find all posts View Profile Close Golly]

Re: Cracks in Inner Guards

Lets hope they did address the issue before the 07 model :| ....