So I've always kept track of how many miles I tend to get on a tank of gas and have averaged 300 consistently for months with the 22RE. On my last tank of gas I got almost 250 miles on a tank and now my current tank I'm at a little less than 1/4 of a tank and have just barely hit 200 miles. I put in all necessary things for a tune up about 3 months ago. Winter just hit and it's been alot colder than before (15-40 degrees outside). I also heard "winter gas" will drop mpg but 100 miles on a tank?!

What I've noticed recently:
When going down a bigger slope in neutral; I noticed the truck slowing down quite much and then checked and there is some good drag on my front tires if I jack them up and try to spin them.

Also my exhaust sounds like it may be acting up a bit. While revving my engine up at an idle it kind of sounds like it's building up pressure and then pushes out exhaust in a larger amount rather than how before it wouldn't be as loud or noticeable. I heard a clogged cat could drop mpg's but I notice no show of loss of power or anything.

I guess I'm leaning more on this drag on my front tires. What exactly in the front brakes cause drag? Is there anything else that could be causing this sudden drop of mpg? Any help would be great!

 

I just replaced the fuel filter on my 22re and am getting better mpg's. Recommended every 30,000 I think. Its often overlooked because its so hard to get to.

 

It generally shouldn't be fuel filter, the older a fuel filter gets the better it filters to a fault. You will actually stop getting fuel. Now a fuel filter could absolutely cause your car to run poorly.

If its obd II and you have a code flash then that might really narrow things down.

What does your exhaust smell like. If you are revving up and all of a sudden it pushes out that sounds like you are actually loading up on a fuel. If you have too much gas you will get poor ignition which will definitely cause loss in power.

If you are getting good ignition but you really think its your exhaust you might want to look to your catalytic converter. The cat is more of a bottleneck in turbo or forced induction cars where you are moving a high volume of air for the size of the motor but if its really gummed up it could be cause your issues. If your cat is clogged it could do 2 things at the same time. Restrict your exhaust flow and completely screw with your o2 sensors.

 

Any ways of checking the cat without having to take it apart and looking inside with some sort of light? As of now my truck has been running just fine as it has always. No losses of power and no check engine lights are on.

 

Must remove cat. to inspect. I have heard stories of charcoal falling out.

 

2nd that, just have to yank your cat out. If your state does emissions you might be able to have an inspection station check your system.

 

Haven't really looked down there. Is it just bolt on, bolt off or more complex to get it off? Also any gaskets I should get before hand? So loss of power isn't always a sign of a clogged cat then?

 

Take it to a shop

 

What year is the truck? Is it California emissions or standard? Try pulling the front O2 sensor and looking for large amounts of soot on it. Also when was the last tune up done? Something also to note is your engine will require more fuel when it is colder outside, it will get up to operating temp slower than normal and will most likely stay below that optimum temp that it is used to. In my 22re, my typical mileage is around 240 mile per tank mainly city driving. The cat is pretty basic to get off, it is just bolted and usually it isn't mandatory to put on new gaskets since they are metal gaskets but it is recomended.

 

It's a 91' and just standard. I'll go ahead and pull the O2 sensor tomorrow and check. Large amounts of soot would be a sign of a clogged cat? I did a tune up about 2 months ago. Yeah I looked up a few threads of some guys saying that they get a good 6-8 mpg drop in winter due to the cold weather and the winter blends of gas and then right when summer comes back around their mpg spikes back up.

 

Soot on the sensor will just cause it to read incorrectly making your ECU feed and take away fuel incorrectly according to the engines needs, I kinda doubt it is the problem as it typically gives you drivability problems as well as increased fuel consumption, but its something else you can check. Could just be the cold weather, but I am jealous since like I said I only get about 240 miles to the tank normally.

 

If you are planning on getting your o2 off tomorrow start soaking the threads with pb blast. If your cat is old enough to consider replacement then everything attached to it isnt going to come off without a fight including the cat itself.

 

I took a few quick looks here and there and yes everything under there is definitely old and bolts looked very rusted so thanks for the info in advance! Just wondering if it's normal to have some drag on the front wheels from the calipers?

 

Some would be normal, I think.

Manual hubs? Are they engaged when spinning the wheels?

How do the pads look? I had a caliper malfunction in which one piston stopped releasing and was pretty much constantly clamped on the caliper which caused serious drag; the pads wore uneven to the point it was metal on metal on one end of the pad.

 

Yes manual hubs and I do not have them locked. I'll probably end up taking a look at them tomorrow as well to check.

 

It will always have some sort of drag from the friction of the bearings and such, you shouldn't be able to spin the wheel and have it freewheel for more than about a second or even a full revolution, the brakes will drag if like bob said the piston stops retracting into the caliper.

 

I would take a look at the wheel bearings while you're in there.

 

had the brake drag on my 94 x-cab. the pistons wouldn't retract all the way, probably from years of dunking in brackish water swapped the calipers for about $100 which was worth it imo.. saved more time and hassle than it's worth to rebuild them.

 

Re-man calipers are so cheap with so many of our trucks out there it's usually cheaper to just buy "new" parts.

 

Do you take the time to record the amount of gallons you put in the tank at each fill.

Then compute the fuel mileage based on the amount of gallons put in next fill up??

Now this is only going to get you pretty close as it is impossible to shut the pump off at the same time.

It is possible your sending unit is going bad hence the lower mileage per tank .

Going by the miles per tank My 4Runner only gets 125 miles from full to empty .

Unless you have a bad gas leak the smell should be pretty bad hard to miss .

Family members or coworkers with a cash flow problem and a hose??

Something else to ponder before tearing things apart.

It does not hurt to have a new gasket for the o2 sensor as well as the 2 for the cat as well along with new hardware for all.