Search for truth- Front Diff and Oil Pan Exposure Question (1 Viewer)

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Diff Kraken

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Hey folks-

I recently had an unfortunate encounter with a rock that surprised me. In my brand spanking new 5th gen 4runner last month a rock about 3-4" tall, paired with a 5-7" dip in the trail, took my truck out of commission at about 8mph. I'm used to hitting skid plates every now and then, but this hit pierced through my OEM skid plate (Toyota calls it a "Splash Guard") and pushed the front diff up into the lower and upper oil pans, cracking all 3 of these components. I shut the truck off immediately after the impact and hopped out in time to see the oil start flowing out of the bottom of the truck.

My question is, all things being equal, do you guys think this rock would have taken out a stock 200 series? I feel like that's unlikely given their reputation in the world's most remote locations. Hoping for a technical analysis/discussion on if this rock would have taken out a 200, or even a 100 series, based on their ground clearance and how their front diffs and diff bracket/s are located/engineered. I might be trying to convince myself to swap this out for a 200 (yes, I know that's a great idea anyway).

And, yes, I know proper armor is considered essential- but this trail is usually considered stocker friendly.

Friends don't let friends buy 4Runners? Is that true?

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Not sure of the answer to your question, but here is a video of LC200 development:



Look at time mark: 0:41.
 
Not sure of the answer to your question, but here is a video of LC200 development:



Look at time mark: 0:41.

I’d say that video speaks for itself.
 
Sorry to hear that!

I'm still interested in the technical discussion, even with the above videos.

I'll even pull off my factory skids for some good pictures of what we are working with, and take some measurements. If you have the ability to take similar pictures and measurements it would be easy to compare.

To start I'm thinking.. distance from skid plate to diff lowest point, distance from diff to oil pan, distance from skid to ground (this is deceptive because our wider track width means being taller doesn't necessarily mean we have an advantage on a crowned trail)

I never even dreamed hitting a rock hard could push the diff up into the engine, but I guess it's worth thinking about. The 120 (modern 4runner) is no 200, but it's not a lightweight either.
 
Sorry to hear that!

I'm still interested in the technical discussion, even with the above videos.

I'll even pull off my factory skids for some good pictures of what we are working with, and take some measurements. If you have the ability to take similar pictures and measurements it would be easy to compare.

To start I'm thinking.. distance from skid plate to diff lowest point, distance from diff to oil pan, distance from skid to ground (this is deceptive because our wider track width means being taller doesn't necessarily mean we have an advantage on a crowned trail)

I never even dreamed hitting a rock hard could push the diff up into the engine, but I guess it's worth thinking about. The 120 (modern 4runner) is no 200, but it's not a lightweight either.
Thanks! I'm really interested myself. I'll have the truck up on a lift this weekend and will be able to post pictures and measurements here.
 
Sorry to hear about your misfortune. It's sometimes hard to tell from pictures, but that rock looks like a non-event. I'd just drive over it with zero concern (but I'm mildly lifted and fully armored). If it is a potential issue, you could pick a line where your diff clears the rock. Tire on the rock, for example. I don't see why anyone would go offroad with stock tupperware. Even the most expensive armor is still cheap insurance.
 
Pics are hard to judge, but that looks like a non event to me too. One in a trillion stuff can happen though. Eventually someone wins powerball and all that.
I’d say never on the 200, but the 200 ships with a factory plastic skid under the oil pan, which I absolutely didn’t trust one bit, so I guess it would be a very unlucky maybe. No way that plastic skid was going to take 6k lbs on a point impact.
 
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It is really hard to judge from pictures, but I can confidently say that I have hit much worse in my LX with the stock skids. Coming on that on the trail wouldn't normally even register with me.

I am pretty surprised that a stock 4R would have any issue either. I have friends that are are pretty rough on their stock 4Rs (base and limited).

Having said that, physics can be a b***h sometimes. It may just be the entropy of the universe that resulted in a very precise impact to inflict the maximum amount of damage.
 
I am pretty surprised that a stock 4R would have any issue either. I have friends that are are pretty rough on their stock 4Rs (base and limited).

Having said that, physics can be a b***h sometimes. It may just be the entropy of the universe that resulted in a very precise impact to inflict the maximum amount of damage.
Well said.

I will say maybe I'm too easy on my rig but the stock skids are doing the job for me so far. I do tend to wheel solo, and have rolled a cruiser in the past, both of which weigh heavily on my propensity for risk taking.
 
Thanks for the thoughts here. Having been going offroad for a few years in my GX470 I’ve had plenty of hits on the factory skids and this hit felt different. It was a huge thwack not a glancing blow like usual. And the small rock didn’t even visually register as a potential threat- I saw it and happily rolled right over it. The impact really caught me by surprise and the oil pouring out after impact was completely shocking. I’m still not really sure how this could have possibly happened but it did.
 
Not sure of the answer to your question, but here is a video of LC200 development:



Look at time mark: 0:41.


BIG OOF at 53 seconds. Damn!
 
Thanks for the thoughts here. Having been going offroad for a few years in my GX470 I’ve had plenty of hits on the factory skids and this hit felt different. It was a huge thwack not a glancing blow like usual. And the small rock didn’t even visually register as a potential threat- I saw it and happily rolled right over it. The impact really caught me by surprise and the oil pouring out after impact was completely shocking. I’m still not really sure how this could have possibly happened but it did.

I bet. Its unfortunate, but you may run that trail 1000 times and never even scrape that rock again. If I were you, I would forget all about it, run out and buy a 200, and never mention it again.
 
I bet. Its unfortunate, but you may run that trail 1000 times and never even scrape that rock again. If I were you, I would forget all about it, run out and buy a 200, and never mention it again.
Wisdom here.
 
Yeah. I think you got unlucky. Odds are it won’t happen again.. so find that 200 and enjoy the ability to easily pass people.

I’ll still pull the skids in a few days if you want. Only a few minutes with the battery impact.
 
Freak accident. I've banged my stock 2012 Trail Edition 4R over similar without issues. 4Runner is a great, very capable off roader. I love mine. That being said, the components on my 200 are considerably thicker/beefier/heavier, but like said above, Physics can be a bitch.

That looks like a mountain trail in the Appalachians?
 
Yeah. I think you got unlucky. Odds are it won’t happen again.. so find that 200 and enjoy the ability to easily pass people.

I’ll still pull the skids in a few days if you want. Only a few minutes with the battery impact.
Thanks, I'll post up this weekend when I take a close look and measurements. I'm also interested in the diff bracket thickness and material. I wonder if the bracket was the weakest link here. I'll take a look at parts diagrams as well. Although, it is very tempting to just grab a 200 and never look back... I did test drive a ‘08 LC w/102k @$36k in November for a potential trade on my 5th gen- wish I had done it! I hesitated because of preferring the driving position of the 5th gen- seats go lower- which I like.

Freak accident. I've banged my stock 2012 Trail Edition 4R over similar without issues. 4Runner is a great, very capable off roader. I love mine. That being said, the components on my 200 are considerably thicker/beefier/heavier, but like said above, Physics can be a bitch.

That looks like a mountain trail in the Appalachians?

Yup, Appalachians. Getting Toyota to send a tow truck up was an "interesting" experience using their call service center that was routing through the Philippines. It took 4 hours to get a tow truck out and the Toyota phone reps couldn't get the location right so they sent out about 4 tow trucks before they finally found me. It was very frustrating but it did work out in the end and they towed it to the closest dealer who worked with my insurance company to get all the needed repairs done. Now I'm worried nobody will pay full price for the truck because of the entry in the Toyota system and carfax, etc. If that's the case I may be better off keeping it.
 
As much as people love their factory skids, my personal opinion is that they aren't a great choice once you go off road anywhere with rocks. FWIW, to the best of my recollection, nearly every 4Runner I have been on trail rides with has had aftermarket underbody protection (one exception was a brand new trd pro 4R, like bought the same week).
 
Just looking at the pics, the rock is not high. Can't even imagine it will cause such a damage. That's sux. Hope things get sort out.
Thanks- yeah, it's all put back together now and running perfectly. The question is do I trust it after this- I had planned to keep this for 20+ years and drive it to trails all over the country and down to baja Mexico at some point, now I'm not sure if I would really trust it in remote areas solo. Do I just throw on proper skids, a mild lift, sliders and bigger tires and call it a day? I assume I would be less likely to get stranded in a 200, or even a 100 just because of the extra engineering that goes into them. But I'm also trying to look at this scientifically and say ok- here's how this truck is built, here's how that truck is built and the differences.
 
If the 4Runner fits your needs and intended uses, keep driving it. The rock gave you the opportunity to refresh your gear oil and install some brand new parts. 4Runners impress the heck out of me. I've only owned one 4Runner (2013), and it was no Land Cruiser, but not everybody has needs or intended uses that require a Land Cruiser. Put some better protection under it and drive the wheels off it.
 

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