Rod Knock on a Stock Engine

[Armond30]

OK. My truck just developed severe rod knock last night, and the rod/crank are pretty much guaranteed to be SCREWED (I have a 3000GT VR4 also, so this noise is no stranger to me.........) But my biggest issue is that my truck engine has 125K miles and is virtually stock (I have the AFe TRD Intake). I always change the oil with Valvoline full synthetic and a Mobil 1 oil filter at every 7,500 mile interval and only took it to the Toyota dealer for oil changes while it was in warranty (from 0 to 60K miles). The Oil pressure light didn't come on while driving, and the dip stick looks like there is still oil in the pan (however it is probably more metal toothpaste by now).

Is this type of failure typical on 1GR-FEs that are driven HARD? I seriously have driven the truck to the limit it's entire life, but I have used the best oils and stayed on top of oil changes. Is this just "expected" or should it have lasted longer?

Any insight is appreciated.

Thanks!

 

[Yardie]

That is not common (that I know of). Do you still have your receipts for the valvoline oil changes? They guarantee your engine for 300,000 miles.

 

[Torspd]

What weight oil did you use? Also, if you run a motor hard you must change the fluids more frequently. Even if they are synthetic.

Here is a little trick. Put some ATF fluid in the oil. Say. A half quart. It is more lubricating than regular oil, and it might help. Trick used on lots of diesel or other older motors. Also, since you have high mileage. You need to use an engine break in additive at every oil change. Has a very high count of ZDDP. That will help as well. Only of course if the ATF fluid works first.

If none of those recommendations help, you might be replacing some parts or a motor. From this point out you need to use a 10w- something. Not the factory recommended. Trust me on that.

 

[Gators Taco]

My Mazda had a knock at start time but went away once the oil pressure got in. It did it from around 40k to the time I gave my truck to the school(240000 miles). Try changing to a 10W30 oil and if you ear the same I would have it look after. Could be a wrist pin or it's at the crank shaft. Good luck with finding the knocking

 

[Armond30]

Thanks for the advice. I should have kept all of my receipts, But I honestly never considered this happening. It's definitely Rod knock. no to ways about it, and it's not going away . It's about 30 seconds from a broken rod . I picked up another engine today from a 4-runner, and I am in the process of moving all the necessary parts over (a lot of the stuff on the 4-runner engine was broken). I also have to figure out some way to replace the brake booster nipple on the intake manifold (broke off during the engine pull.......still kinda confused as to why there were no engine pulling loops or hooks on this engine). oh well. There is always a first time for everything I guess.......

 

[x20Runner05]

That knock is not common. I have yet to see one 4.0 motor tacoma with a knock. I myself have driven my truck hard and as a mechanic i have added lil tranny fluid amongst my synthetic oil. If i was to be looking at the truck i would prolly end up pullen the oil pan down and take a peak at what the bottom end looks like. Might even have hunks of metal in there and you dont even know it.

 

[rich017]

I highly agree on pulling the oil pan. Doing that will most likely reveal what the issue is.

 

[x20Runner05]

Thanks for the advice. I should have kept all of my receipts, But I honestly never considered this happening. It's definitely Rod knock. no to ways about it, and it's not going away . It's about 30 seconds from a broken rod . I picked up another engine today from a 4-runner, and I am in the process of moving all the necessary parts over (a lot of the stuff on the 4-runner engine was broken). I also have to figure out some way to replace the brake booster nipple on the intake manifold (broke off during the engine pull.......still kinda confused as to why there were no engine pulling loops or hooks on this engine). oh well. There is always a first time for everything I guess.......

Alot of times you can use a chain and some long bolts but make sure they strong enough to handle the weight and not screw them through the bad motor or good motor. With the bad motor you can tear it apart and rebuild it for minimum money. Just use the intake manifold that has the nipple off your engine in the truck with the knock. Sometimes pulling stuff like the intake off make it easier to not break shit putting motors in or out.

 

[Armond30]

Thanks for the advice guys, but I have already swapped out the engine for a salvage yard unit from a totaled 05 4-runner. motor had right under 60K on it and appears to run perfectly fine (using my intake manifold and iridium plugs). There is no question what is wrong with my old engine. At least one rod bearing is destroyed, and at least 1 rod is ringing on the crank like a bell. it's "very much done". pulling the pan would just show how much bearing material was turned into dirt at this point. I figure the failure is from years of high G cornering (not joking on this one). My guess is that the pan doesn't have any special baffles or trap doors to keep oil around the pickup under heavy side loads, and enoguh hard corners enough times at high RPM will take it's toll (That's actually what I was doing when the motor went). I always took it easy on the truck when the motor was cold, and I always used the best oil and an oversized oil filter, and the truck only had an Air filter kit for engine modifications, so that's all I can come up with . Oh well. I am highly interested in selling the truck now 'though if anybody knows anybody that wants a high mileage SWB 05 for average selling price. I think I am going to choose a different daily driver vehicle. It's a fun truck, but I think my time with it is over.

 

[Murderface]

Yup ur not the first nor last one to spin a main bearing from hi G turning at hi rpm. We have a few members that have done that and with low miles too so u having hi miles may have contributed to it's demise.
We have a member working on a new pan with trap doors and baffles to address this issue as we speak.

 

[Torspd]

The oil pan shallow design isn't limited to just the Tacoma. The Scion tC also is plagued with the same problem. One after market company sends a deeper designed pan with their turbo kits, for the car. Gods you got it fixed up though. What a hassle.

 

[burnboy]

Come on coupe! Lol