Auto Transmission Fluid As Fuel Additive?

Joe B

Veteran Member
Joined
Oct 13, 2000
Location
Woolrich PA USA
I've been driving VW diesels for 11+ years now. My first one was an 89 Jetta (52hp). My mechanic used to recommend dumping a quart of auto transmission fluid in the tank every so often. Is anybody doing this with the TDI's?

------------------
 

dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
Joe, you hear people doing this all the time. A/T fluid is meant to be used in an A/T and is not intended to be burned in a motor. It is far from ashless.



------------------
96 TDI Wagon, ABS, emerald green
00 Jetta TDI GLS, silver arrow, CWP, LUX1, etc, etc.
 

Turbo Steve

Top Post Dawg
Joined
Jan 11, 2000
Location
.
Use some Marvel Mystery Oil or 2-Cycle Oil if you want a pure fuel lubricant.

There are plenty of additives out there that also lubricate well and you want something that is definately ashless.

ATF worked on older diesels because they don't have the emission equipment the newer TDI's have, but should no longer be considered.

Get some plain ol' dino-based 2-Cycle Oil from Walmart at about $5.00 US per gallon. It's ashless and very inexpensive and made for them by Pennzoil / Quaker State.
 

Joe B

Veteran Member
Joined
Oct 13, 2000
Location
Woolrich PA USA
Turbo, does the 2 cycle stuff cause smoking? I have recently begun using a Power Service additive. It's about $10/big jug at Walmart. What ratio of 2 cycle oil/gallons of diesel would you recommend. My 97 Passat supposedly has an 18.5 gallon tank, although I understand I can do better with the vent trick.

------------------
 

Universe

Active member
Joined
Nov 24, 2000
Location
Danbury, Ct , USA
I think your better off with an additive designed specifically for diesel fuel. The higher quality 2 stroke oils are fine I'm sure. The marine 2 stroke oil is far from ashless. I've used it in my air cooled 2 strokes and it does not provide the same performance, much more smoke and ash. I would definately stay away from atf in a modern diesel engine such as the tdi. Most auto parts stores will have a big selection of what you need.
 

Turbo Steve

Top Post Dawg
Joined
Jan 11, 2000
Location
.
Joe:

I've had no problems in running 4-oz. of Walmart's 2-Cycle Oil in my TDI in the past. It says "ashless" right on the front of the bottle.

Lucus makes a nice lubricant too, but it's a lot more expensive.

If it would make you feel more comfortable, just use Marvel Mystery Oil with 6-oz. per tank, since it's thinner than the 2-Cycle oil. Power Service's Diesel Fuel Supplement doesn't appear to have a lot of lubricating properties in their formulation, hence I use an extra additive for pure lubricating purposes.
 

Joe B

Veteran Member
Joined
Oct 13, 2000
Location
Woolrich PA USA
My old injection pump crapped the bed at 188,000 miles. The mechanic said the seals probably went bad because the "new" fuel was low sulfur and sulfur in diesel fuel acts as a lubricant. I assume the TDI's were designed to run on this low sulfur stuff. On the other hand, I have seen some postings suggesting that high sulfur (off road) fuel may kill the TDI components due the high sulfuric acid content. Anyone?

------------------


[This message has been edited by Joe B (edited December 23, 2000).]
 

ralphwood

Veteran Member
Joined
Jul 15, 2000
Location
Sanger, TX USA
Hi,
People have been using ATF as a fuel additive for a long time but that doesn't mean it is any good. If you have ever seen overheated ATF you probably wouldn't want it in your fuel. It's some nasty stuff.
Cummins has a system for large diesel engines where a computer takes used oil out of your crankcase and pumps it into your fuel tank. Some new oil is then pumped into the crankcase from a tank of new oil. This requires a better filtration system than the stock filter system. Adding used motor oil to the fuel will improve the quality of the fuel but it must be mixed good. A pump can't handle a shot of motor oil.
The process of removing sulfur from diesel fuel lowers the natural ability of the fuel to lubricate. It's not that the sulfur is a lubricant. I have considered putting a small valve and tee in the line going to my bypass filter and fuel return line going to the tank. With the engine idling I could open the valve and pump a qt of oil into my fuel tank then add a new qt of oil to the engine. I have a killer fuel filtration system. Plus my engine oil is clean. I've been dumping a qt of used oil in the tank not being used then filling it up with fuel. This system is a nuisance when traveling. I don't like hauling used oil. Some commercial fishermen have a used oil tank that they keep full of oil they scrounge from oil change places. They inject the used oil into the fuel line going to the engine. They are mostly interested in cutting fuel costs. The used oil is cleaned with a large paper towel filter. I make no recommendations for TDI. Just a little food for thought.

Ralph
 
Top