Ford Power Stroke Nation banner

What kind of symptoms can you get if you leave the oil in too long for 7.3?

3K views 28 replies 10 participants last post by  clydesdale 
#1 ·
Idle knock?

I have 8500 miles on the oil with a bypass system. Analysis says the oil is fine, but I am curious if it causes a knock.
 
#4 ·
If you have a really picky engine like one of mine was it will randomly shut down on ya until you change it out
 
#5 ·
Hard starting... IE.. longer cranking times. it happens with mine @ about the 5K mark with 5-40 synthetic rotella

i've read around, some guys go 10K with the bypass system... but idk... some trucks at my work go 5-25K miles on Rotella 15-40... but that's big cat and cummins engines...
 
#6 ·
everything said above plus you could end up clogging your IPR.
 
#7 ·
Idle knock is not a symptom eh? I was hoping. I have 8500 on now, with rotella syn 5/40 and a bypass. I may change it anyway.
 
#17 ·
That is just not true.

My truck runs fine on Amsoil I have stated this before I am on my 4th oil change going on 85k.
Oh yea it runs like a top and I drive it as if I had stole it.
Bill
 
#11 ·
Can you post your Oil Analysis Report so we can get a better understanding if this is oil related or another issue?

If you like you can e-mail it to me and I'll post it or go over it with you. Curious about your CST@100 Viscosity and oxidation values.
 
#12 ·
Wouldn't it be a kick in the ass if an oil change fixed your truck. I would change it tomorrow.

Never knew about this with the issue you were having.
 
#13 ·
I will absolutely sh#t myself if this knock is from the oil. It drives me nuts that it is totally beautiful sounding until the oil hits 170. I drove it today to pull the trailer around and I had a couple of short stops. The oil never got over 160, sounded beautiful. I am changing the oil tomorrow.
My wife sent White Buffalo my analysis. It did have the lowest viscosity at 100 celcius of all of my prior samples. I am curious to see what everyone in the "fluids" forum thinks.
 
#14 ·
E-mailed it back to you a few hours ago......analysis looks very good.
 
#15 ·
Are you able to post it up here? I did notice that the viscosity numbers at 100 celcius were the lowest ever. All the wear stuff looked great. But I wonder if changing the oil will have an effect.
 
#16 ·


clydesdale,

Oil analysis looks very good. All wear numbers are low, a very good report. Copper is nice & low, good to see.



The oil viscosity is getting close to a 30 weight oil. The CST@100C reading on your report was 12.72. That is at the low end of a 40 weight oil. The range for a 40 weight oil is 12.5-16.29. You can see this yourself on the chart posted on PSN in the Fluids Discussion Forum, sticky on the Comparative Viscosity Chart. Here is the link:


comparitive viscosity chart - Powerstroke Nation


You can push this oil a bit further but not much. I would change it if it was my truck. A 8,000+ mile oil run on a PSD is a damn good run. No fuel, water or antifreeze – that’s great – your PSD looks nice & healthy. TBN retention was good also, didn’t drop much from baseline at all.

Rotella Synth 5W-40 is a good oil for the Powerstroke. I don't believe your knock is oil related.

"I will absolutely sh#t myself if this knock is from the oil." = me too........:cool:
 
#18 ·
Could the knock be fuel related or the classic noisy #8 LL injector? You still have the stock injectors correct?

But I would think the Reg Ruturn & the fuel system would have cured that.
 
#19 ·
OK, great thanks. I'll change it over the weekend and let you know.
 
#20 ·
If you can find it get a 5w30 synthetic I think Mobil has one you truck will love it so will the injectors/turbo.

Bill
 
#23 ·
I need to be your oil salesrep/supplier!.....
 
#22 ·
The knock was VERY slight, hardly noticeable and started shortly after the RR and I figured it was because I still had the LL. It started to get worse lately, so I ran a CCT and #8 failed and had 2.9%-4% on rotational velocity. I changed the LL for a standard AD and it made no effect. The truck runs fine, just has this new bleepin knock that was not there until about 1-2k miles ago and is only there when the oil gets past 170 degrees. Life would be so good if an oil change would get rid of it, but probably not going to happen.
 
#24 ·
Using Auto Enginuity?


How was the Buzz test and what does the CCT look like with the new injector in?
 
#26 ·
Yep, using AE. The buzz is fine on all 8 before and after LL change out and the CCT and rot velocity look the same. The compression on that cylinder was 375 on a stone cold engine. I only checked the compression of that one cylinder. The truck runs fine.
 
#27 ·
Well, oil change did not solve the problem. Changing back to black cps did solve my CCT issue.
 
#28 ·
How's the knock?
 
#29 ·
The knock is still there. I have not driven it since the weekend, but I am sure it did not go away. I am toying with the idea of building an injector breakout box and trying to isolate where the knock is coming from. I am first going to look at my fuel pressure and see if adjusting it will make any difference.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top