can a ford ranger tow trailer on steep mtns rds?

Slowly but yes. Does Ford say your Ranger is four down towable?

Going up, you'll work the engine and spend the entire climb in boost. I doubt power will be an issue, but wear might be in the distant future if you tow often enough.

Going down I expect you'll be working the brakes because I don't imagine that engine/trans will offer enough hold back for the truck and 4500lb trailer to be of much use. Sounds like you might be setting yourself up for some white knuckle descents, but I've never tried that combination and I doubt many others here have.

I know my old Ecoboost 3.5 struggled to hold speed coming down 7-8% grades with a ~6K trailer, or at least scream doing it and still required some assistance. Your smaller engine will be notably less effective.

If you don't mind pedestrians passing you it should be just fine. Thats a lot of weight.

jahupe make good points about DEcending.

Keep the trailer GVWR within your tow rating for best results.
Watch the hitch weight does not use up all your payload.

bgum wrote:
If you don't mind pedestrians passing you it should be just fine. Thats a lot of weight.

So apparently 270 horsepower is insufficient??? That’s more than the original v10 made.

OP- the same motor has been in the Explorer for some time, and I’ve never heard a single power complaint.

I should have added, with the tow pkg added it is rated capable of towing 7500lbs. however I am very concerned weather this truck can handle my load going up steep inclines and also going down hill. This same pkg has been used in the 2019,2020 and now the 2021 models. Tom

Weather is an additional factor to consider IMO.

Since it's within the specs from the factory, it's a fair bet that ,,,,
Yes it will pull it.
Will that little 4 banger be screaming?
Most likely.
Will it provide enough drag on downhill slopes?
Likely not , without a lot of braking.
Do they offer a Tow/haul mode on those? Some method of forced downshifting would make a big difference, and with it, it may not be bad.

carringb wrote:

bgum wrote:
If you don't mind pedestrians passing you it should be just fine. Thats a lot of weight.

So apparently 270 horsepower is insufficient??? That’s more than the original v10 made.

OP- the same motor has been in the Explorer for some time, and I’ve never heard a single power complaint.

And I had a V10 and in some situations pedestrians could have passed me. Can it pull it-sure it can-will I be comfortable-not really.