Well, let's look at the rules.
Your carrying capacity is 10 * STR. So the average human can carry 100 lbs without being encumbered and deadlift 500 lbs. Which is pretty good. A human with a 20 STR, the limit of human ability, can carry 200 lbs and dead lift 1000 lbs. The world record for a deadlift is 1015 lbs, btw.
The Ogre is a Large creature, so their numbers are doubled. The 18 STR Ogre can carry 360 lbs and deadlift 1,800 lbs. The typical hill giant with a 19 STR can carry 380 lbs and deadlift 1,900. Incidentally, per the article Ogres are 9 feet tall, and it mentions AD&D Hill Giants, which were only 10 1/2 feet tall in 1e, and 16 feet tall in 2e.
A Storm Giant is almost certainly a Huge creature, which means scores are doubled again. If they have 25 STR, they can carry 1,000 lbs and deadlift 5,000.
Difference between average human and human limit: 100/500 lbs.
Difference between human limit and average Ogre: 160/800 lbs.
Difference between average Ogre and average Hill Giant: 20/100 lbs.
Difference between average Hill Giant and average Storm Giant: 620/3,100.
So, the difference between a normal human and a really strong human is 200%.
The difference between a hill giant and a storm giant is 263%.
If we say a Dragon is Gargantuan and has 30 STR (monster limit), they'll carry 2,400 lbs and deadlift 12,000 (240% stronger than Storm Giant).
I dunno. The only number that seems off to me is the average human deadlift. x5 might be a bit much, but x2 is maximum carrying capacity. x3 might work. That's still 300 lbs, but seems a bit more feasible, even if it's not reasonable.