Ford Taurus SHO engine knock

[bmwtechguy]

A friend has been over to our shop several times now over the last couple of years with his brother to talk car stuff and yesterday his brother Ben mentioned that he has one of these cars. We started talking oil and I found out that he is a diehard Mobil 1 guy. He described his driving style as very aggressive and runs up to redline sometimes. At about 140k miles on a well-maintained car, he was driving hard and engine oil light flickered and he immediately noticed the engine knocking so he shut it down. He had about 3000 miles on the oil, the crankcase was full (5W-30) and he goes about 5000 miles on an oil change. This was about a year ago when this happened and his car had no engine mods. He put in another engine with 80k on the clock and switched to Mobil 1 10W-30. He said he still drives it hard. He lives in northern OH and travels here (flys) several times a year to do machinery upgrades/repairs on filling equipment at a local plant. He's a really sharp guy and knows technical stuff-hydraulics, electronic controls, programming, etc. He's probably about 25-30 years old. My question is, are these engines (Yamaha?) prone to this type of problem? And, why the heck did he stick with that oil if it did not protect his engine the first time? Maybe this engine would be a good candidate for some Redline? I let it go and did not make any suggestions, but now after thinking some on it, maybe I should have. I have no experience with that engine. Any thoughts or experiences?

 

[brianl703]

Could it have been an oil pump failure?

 

[Virtuoso]

Probably spun a rod bearing. Certianly not unheard-of in these high-strung SHO engines. Some SHO enthusiasts even consider them almost preventive maintenence. On one of my old SHOs; the oil pressure light would come on at idle after running it hard with Mobil 1. A quick switch to Castrol GTX and I never saw the light (with engine running) again. Mobil just didn't hold the pressure while hot in that engine.

 

[Reg# 43897]

Yes, Yamaha engines. I wonder how GC would work in one of 'em...

John.

 

[bmwtechguy]

Yes, he did say he believed the oil pump may have failed, but that he never had any warning signs until it happened. I would think that he might have had better luck with GC or Redline in that engine driven hard. Isn't the HTHS for GC higher than the 30 weight Mobil 1 oils?

 

[olympic]

I own a couple 3.0L SHO engines. He definitely spun a rod bearing. Oil pump failure is unheard of in these engines. As stated above some owners replace the bearings as standard maintenance. Although there is no hard evidence, most of the gurus who work on SHO's on a daily basis recommend against Mobil 1 in this engine stating that they see more bearing and cam wear in engines that use this oil.

 

[bmwtechguy]

So I guess my question then is, what oil/filters do you or others that may have experience with the SHO, use to prevent what happened here? Or maybe you guys just don't drive the snot out of yours like he does.

 

[Virtuoso]

My MTX SHO burned a fair amount of oil; so I kept it full of Castrol GTX (cheaper). The ATX SHO I owned really didn't burn much; so I used GC in that application. Napa Gold/Wix filters were used on both.

 

[SHOZ]

Rod bearing wear is normal on the SHO motors. They have a low pressure/high volume oiling system and that along with the higher rpms the engines see will cause the early wear.

Motorcraft filters are always the best. Most 5w30s are good whether synthetic or not. Mobil One 5w30 is a bit on the thin side for them though.

I use 5w40 in mine.