Diesel / TCW3: Anyone else seeing real results?

Status
Not open for further replies.
D

DoubleWasp

Joined
May 21, 2012
Messages
6,762
Location
Fort Lauderdale, FL
I've been playing around with using TCW3 in my diesel vehicles for some time, and I've undeniably seen a 1-2 mpg improvement with it than without it.

Looking at it from the other side of the table, I can't argue against it. Even doing things like running half the fleet on it, and half off, and then switching both halves around, there's 1-2 mpg gain with it, that is demonstrably lost when not used.

I've found my best results using a full quart in a 40-gallon sized tank.

Use with gasoline engines has been mixed. I get 2mpg improvements with some, and absolutely nothing with others.
 
160:1 mix ratio seems a bit on the strong side. Most people that do this are doing 200:1 or leaner.

I have used 2-cycle oil in diesels before and noticed positive results. I don't believe you're seeing a placebo effect. I think it really does help in some manner, especially with the dry fuels that are produced today.
 
Ive seen improved mpg with 2stroke oil in the fuel tank of my 4stroke, dosed at approx. 150ml per 40 litres.

I wondered at the time if it was due to the 2stroke oil changing the properties of the fuel or if the improved mpg was a result of improved compression as seen with a wet compression test?
 
Been thinking of trying this in my (petrol engined) car and motorcycles, for (potential) wear reduction rather than MPG, which I probably wouldn't be able to verify anyway. With a diesel I suppose it'd also improve the injector pump lubrication.

I'd been worried about the effect on emissions, but I passed the (private) emission test recently when I'm pretty sure I shouldn't have, so apparently that isn't likely to be a problem as long as I stay away from govt testing centres.

2-stroke oils are still very available here, but there's a government push to get 2-strokes off the roads, with talk of bans, so that might not last. I'll have to look into whether any of the available oils are TCW3 certified
 
Last edited:
I use it in both cars (petrol and diesel).

I'm wondering if some of the papers that I've linked to on Friction Modifiers in fuel transferring to the oil film on the cylinder walls has some merit.
 
Originally Posted By: Shannow
I use it in both cars (petrol and diesel).

I'm wondering if some of the papers that I've linked to on Friction Modifiers in fuel transferring to the oil film on the cylinder walls has some merit.


It might have some merit. I'm thinking during the period it takes the oil in the sump to reach operating temps the TCW3 might be helping reduce ring and cylinder wall wear. My only fear is does it increase the likelihood of the rings coking up in a gas engine? Some say yes, others no.
 
It might even reduce the likelyhood of coking, if you can limit the amount of combustion gasses to reach down there, and by keeping the rings oiled.

All I know is the oil level in the car stays at the level I put it, and I typically run 10k oci. Coked rings won't allow that.
 
Originally Posted By: FowVay
160:1 mix ratio seems a bit on the strong side. Most people that do this are doing 200:1 or leaner.

I have used 2-cycle oil in diesels before and noticed positive results. I don't believe you're seeing a placebo effect. I think it really does help in some manner, especially with the dry fuels that are produced today.


The real needs was diesel engines with mechanical injection pumps like Bosch VP44.
 
TCW3 is ashless, diesels make soot. In diesels is TCW3 a cetane booster? I dunno, I'm just tossing ideas off the top of my head.
I know of a guy running a carbed jeep over high altitude passes in CO used it. He claimed modest gains in MPG and performance.

A 2 stroke gets all it lubrication through fuel. It works for that. Why wouldn't it add lubricity in a 4 stroke?
 
Originally Posted By: Jetronic
It might even reduce the likelyhood of coking, if you can limit the amount of combustion gasses to reach down there, and by keeping the rings oiled.

All I know is the oil level in the car stays at the level I put it, and I typically run 10k oci. Coked rings won't allow that.


I thought of that too and that's what I'm leaning toward and why I still use it. I think the reward far outweighs the risks. I also believe it helps prevent the wear I mentioned earlier while the engine is getting to operating temperature.
 
I tried it a few times at 400:1 it seems to give a small increase in mpg but nothing you couldnt say was weather effect.

maybe 2-3% better

160:1 is very strong for a gas engine.
 
Why the insistence on TCW3?

I'd guess this is because its low ash, and ash is felt to be likely to negate any wear-reduction benefits?
 
Based on usage of TCW3 when I had my diesel: EGTs were higher, low and mid-RPM performance increased at the expense of high RPM performance, engine was quieter, boost response was different (VGT).
 
Ok, so there's a possibility I'm not insane. Excellent.

I'm sticking to ashless TCW3 because some of my diesels have DPF'S, and ash is the devil to them. The DPF'S can't rid themselves of ash.

I know my mixture seems kind of high, but the results cannot be argued with. My higher output diesels seem to love this the most.

Give them a quart on a full tank, and a good spanking over the road, and they deliver peak fuel economy.

Where ring coking is concerned, my diesel 3-4 gallon dumps lose about a quart over 10-12k miles. As a previous poster stated, coked rings generally don't allow this.

For some reason, my carb and TBI engines respond better to this than my port injected engines.

Thanks for all of the input.
 
Originally Posted By: DoubleWasp


For some reason, my carb and TBI engines respond better to this than my port injected engines.



Perhaps the 2-stroke oil is tending to concentrate on the intake manifold surface, and then transfers (via the intake valves) to the cylinder head and walls, as a moving surface layer?

Direct injection would be into the cylinder free space where a lot of it would just get burned.

Pure speculation of course, and there are probably lots of reasons why it couldn't happen.
 
Status
Not open for further replies.

Similar threads

Bailes1992
TCW3 in Diesel
Replies
8
Views
2K
dumkid
J
Wynns Diesel Power 7
Replies
3
Views
2K
MattPersman
P
Mixing Diesel additives
Replies
13
Views
2K
NashNative
Z
Supertech,valvoline,pennzoil tcw3.most detergents to mix w/gas?
Replies
6
Views
3K
Dave1027
S
Which amsoil for outboards???
Replies
10
Views
3K
oilboy123
Back
Top