jjfred2112

Alright, I will try to be as thorough as possible here. I can't find any other posts or threads discussing this.

I bought new Cooper Discoverer ATP LT 265/70R17 tires a few months back for my 2015 XLT 2.7. Obviously, these tires are a bit larger than the stock. I have been reading online, but can't find anything specific about these tires on my vehicle, and people are all over the place on recommendations. Some people say to stick to what the placard says while others suggest adding more PSIs to the tires because they are larger.

The placard suggest 35PSI for front and rear. My tires are currently between 34-36PSI "cold."

The tire says 80 PSI is max. Yes, I know that is with max load.

I don't haul much, if at all.

The tires seem a bit squishy (even when I poke with my finger) and at times my truck seems sluggish, and ever since I got the tires my gas mileage has gone down. yes, I understand with the slightly larger tires this will consume more gas, but it just seemed to have gone down significantly more for me.

I need recommendations or advice. I checked the Cooper website but couldn't find any helpful information on there.

Any questions, please ask.

bhamilton

Where did you buy them from and who installed them? I'd ask them first.

jjfred2112

I bought them from Discount Tire and they installed them.

chadderkdawg

I run mine at 30ish psi

jjfred2112

30ish seems low. Like I mentioned, mine are between 34-36 PSI and seem squishy when I poke the tire walls.

On another forum, but for Rams, a guy was saying he did 45PSI and his truck is running great with the same tires.

Just want to get feedback from those that drive Fords.

Schlotzky

My factory LT Load Range C truck has 39PSI on the door placard. I would suggest starting there. LTs do need more pressure to support the same load, so that's why Ford spec's them a little higher, even though the load carrying capacity is about the same. They're also quite a bit heavier due to additional plies and heavier duty construction, so that's likely what you're feeling is the additional rotating mass. You can help offset some of the loss in mileage by going up in pressure at the cost of ride softness, just don't go crazy.

flyin51

iTrader: (1)

When I put those on my 97 f150 in 285 they told me to run 45 PSI. Mine are 10 ply.

Schlotzky

Yeah, it depends on the load range. 10 ply would be a Load E I believe, which would want a little extra pressure over my factory C. What's the load range of your coopers?

jjfred2112

Mine are 10 ply, as well. So load range "E."

SPOAT

Read this...............

https://toyotires-1524598101.netdna-...s_20151020.pdf