Tire wear: Inside and outside, on both sides?

Hello,
'When I had new winter tires installed last week, I noticed the following phenomenon on the front (old) summer tires: The tread on the tires was completely worn down on the inner and outer edges, leaving almost nothing. In the middle, the tread was still okay, and this was the case on both sides of the vehicle. How is that possible? All the bearings and tie rod ends are in good condition, and the tire pressure was always correct. I only had the new winter tires on for a short time, and already the rubber on the edges was starting to show signs of wear. I switched them back to the old tires... until I figured out what was causing it. Does anyone have a tip? What could be the cause?'
Sure, here's the translation:

'Hello'
Jens.

Volkswagen Golf 4, 1.9 TDI, AGR (heated seats), 1998, 200,000 km.

What tire pressure do you use?

Hello Julian,
1.9 bar, as indicated on the fuel tank cap. All four tires, because I usually travel alone.
Sure, here is the translation of the text from German to English:

'Hello'
Jens.

jensg wrote:

.... 1.9 bar, as indicated on the tank cap. ....

I believe this manufacturer's specification is too low for a car weighing 1.5 tons.
I drive with a tire pressure of 2.3-2.4 bar, and my tires wear down evenly.

I can only say that, in my opinion, the tire pressure specified by the manufacturer is only a guideline. For example, on my old 1986 Passat 1.8, for many years, the factory-recommended pressure was used with a full load, but with a reduction of 0.1 bar in the front (always measured with cold tires) and 0.1 to 0.2 bar below the recommended pressure for a full load in the rear. This simple formula also works for winter tires. I drove one season with winter tires using the factory pressure, and the result was the same as yours: disproportionate wear on the outer and inner edges.

My (naive) calculation:
The slightly higher pressure at the front helps to relieve the stress on the tire sidewalls, which are already heavily loaded in front-wheel-drive vehicles.
'Having more pressure at the rear reduces the need for adjustments when unexpectedly carrying a load, and even in normal operation, the significantly higher pressure (compared to the recommended pressure for an unloaded vehicle) has a positive effect because it results in less lateral force (which is a good thing!), giving these notoriously understeering VWs a bit more neutrality.'

Besides, it saves some fuel.

(as I said: just my quick calculation )

Good night!
herwig

I recommend visiting an axle weight scale.

Since I adjusted the tire pressure to match the actual axle load, the car feels much more stable and planted on the track.

I find it puzzling why the recommended tire pressure for the rear tires is 2.5 bar when the front tires, with a load of 740 kg, are recommended to be at 2.0 bar, while the rear tires only have a load of 550 kg.

@herwig
The high pressure at the rear actually counteracted the understeer. Lively oversteer...


CU Gremlin.

Hello Julian,
1.9 bar, as indicated on the fuel tank cap. All four tires, because I usually travel alone.
Sure, here is the translation of the text from German to English:

'Hello'
Jens

Wow, way too little...

Fill the tire pressure to the recommended level for a full load, ideally around 2.6 bar all around when using 205/55 R16 tires, as I used to do with my Golf 4.

It's better to have too much pressure than too little in the tires. Most common sizes can handle up to 51 psi = 3.5 bar (see the tire sidewall!), and that pressure can be used without any problems if you're willing to sacrifice some comfort.

I recommend visiting an axle weight scale.

@herwig
The high pressure at the rear actually counteracted the understeer. Lively oversteer...

CU Gremlin

@gremlin

Yes, once you've driven a car with rear-wheel drive...

With the Bora, which generally has flatter tires, the high pressure at the rear doesn't have as much of an effect, while the older Passat, without the pressure trick, relentlessly drove straight ahead, especially on snow. A driving instructor gave me the idea to try higher pressure at the rear - I was grateful to him in every snowy Austrian curve for the remaining eight years of the car's life .

Hi, thanks for all the contributions.
'But I don't think it's related to the tire pressure; I've been driving with this pressure for 200,000 kilometers. It's actually very comfortable... I've also tried higher pressures, and it feels like driving on wooden tires.'
And the wear was only noticed during this year's tire change. Unfortunately, the old winter tires are gone; I couldn't examine them, but I believe they were worn fairly evenly. So, it could have been happening for about a year or so (i.e., 30,000 km). That reminds me, the car had new shock absorbers installed sometime during that period. Could that be related...?
Good night, everyone!
Jens.

Hello!

I once had a similar problem where the tires were wearing down more on the outer edges (left and right sides of the tire) than on the inside. The solution to the problem was to have the wheel alignment adjusted.

What do you think would be the optimal tire pressure for a Golf III sedan TDI 1Z with 185/60 R14 tires (like mine), which is mostly driven unloaded?

Greetings from Nuremberg,
Mathias.

1.9 bar is clearly far too low!

That's why the tire is wearing out on the edges.
In short and exaggerated terms: the tires are curving too much inward, causing the outer edges to wear down extremely quickly.

Furthermore, fuel consumption increases significantly, and the driving characteristics deteriorate drastically, so there's no question of comfort.

I've seen many tires ruined in a single summer or winter due to insufficient tire pressure and the same wear pattern.

I drive my unloaded G3 TDI sedan with...

Summer tires (185/60 R14):
Front: 2.4 bar.
Rear: 2.3 bar.

Winter tires (175/65 R14):
2.5 bar at the front.
Rear: 2.4 bar.

When fully loaded (which is very rare), I drive with a tire pressure of 2.6 bar all around.

It has proven to be a good compromise for me between comfort and even tire wear, plus fuel savings.

Best regards, Georg.

The wear pattern is typical for insufficient pressure! And the stated 1.9 bar (but for what tire size, exactly) fits that description.

Roughly speaking, you can easily run 0.3 - 0.5 bar higher pressure. The comfort might be slightly reduced, but the wear will be more even, the rolling resistance will decrease, and the transmittable forces will generally be higher, especially the lateral forces.

I drive a 1.9 TDI Vento (90 hp).
It has a tare weight of 1185 kg, and...
According to [source/manufacturer/etc.], the tire pressure (for tires of size 185/60 R14) should be...
VW recommends a tire pressure of 2.2 bar in the front and 2.0 bar when the vehicle is empty, increasing to 2.2 bar when fully loaded in the rear.

It drives more like a pregnant cow.

Therefore, I'm now setting the front tire pressure to 2.6 and the rear tire pressure to 2.5.
It's (purely subjectively) the optimal compromise.

Tires generally wear down in a similar way.

(Note: I also tend to drive relatively fast in curves.)
Even so, the tires will still wear out.
slightly more pronounced on the outer edge.

Hello.

I even run 3.0 in the front and 2.7 in the rear, all year round.

Summer tires are size 215 with a relatively low profile, which means there's a higher risk of wearing out the inner edge. (On the 3.0 and 2.7 models, however, the wear is very even.)

The winter tires are size 185, mounted on a rim that is designed for size 195 tires. Consequently, the tires have a higher aspect ratio to bring the wheel diameter back into the standard range. They also wear very evenly (3.0, 2.7).

I'm mainly doing it because of the fuel consumption/draft.

@Above

Why don't you specify your actual tire dimensions?

Because 185/55 15 is standard, and I wouldn't describe it as "intended for 195" .

m;

um...

because I could never remember what each term actually meant (like the 'port/starboard' problem), and my knowledge about tire/rim width and the inch size of wheels just stops there.

So, without rambling, I wanted to express:

With a 195-size tire, the tire sidewall would be perfectly vertical to the front of the rim on this wheel.
With the 185-size tire, the sidewall tends to bulge outwards, which is compensated for by using a higher sidewall/tire size. And that's exactly the measurement I'm missing.
That's why I'm rambling like this.

I thought that, with specific pressures, it might induce certain degradation characteristics.

'Some proletarians drive around on their 316 BMWs with those wide, flat rims, those Kononenrohre, as they're called. They're definitely using tires that are too narrow in proportion to the wheel, and to compensate for that, they put on what are called 'tractor tires,' where the high tire sidewall makes up for the lack of width. And the overall wheel diameter is still correct.'
It really looks like 'Wow, man' .