I towed our 21' travel trailer home last weekend, but I could not get my truck over 60 m/hr is the 5.2 Lthat guttless that it can't pull a trailer??

or could there be something wrong.

 

I feel your pain. I've got the 5.2 in a 4x4 reg. cab and have the same complaint, but yes there can be something wrong.
How long have you had the truck? Are you comparing it at new condition and see a power drop?
First have to ask about a tune-up?
Check the cat out for clogging if you got some miles on it.
Check for the infamous plenum pan leak.
O2 sensors - can be cleaned up and good as new.

 

Before my cat was bad, I would tow a 3000 lbs trailer and under low throttle accelerations I honestly could not tell it was there... it was noticeablely slower at full thottle than with out the trailer, but it wouldent be considered gutless.. I could hit 100 easy with my trailer...

Although, when my cat was plugged, it really dident have much more umph to pull that trailer, it was pretty hard to get going...

I have the 5.2 also...

 

wtf...i can BARELY touch 100 with my5.9L reg cab short bed 4x4...WITHOUT a trailer, and from 70 to 100 it takes forever. might have to check out my cat...

 

I have a 97 5.2 and it was pretty gutless when I bought it. I installed a Flowmaster dualexhaust kit but it didn't help much. Then I installed headers and a MagnaFlow Hi-Flow cat and it brought the truck to life! It takes no time to get from 60mph to 90mph. The first time i towed a car and trailer with the new exhaust I was going about 85 using half the pedal as before.
Cat makes a BIG difference!

 

I've hit 100 with my trailer before too - not downhill either, it was level ground... "Course, you gotta have a good trailer for that... They like to get squirley if they're not built right...

I've pulled over 10,000lbs on several occasions with my little 5.2L with no problem... Even in overdrive, although if you're on hilly terrain, I recommend stickin with just 3rd... Oh, and I have the 3.55s in the rear...

Aside from exhaust, there are no mods to my truck... But the exhaust is killer - 2.5" true duals all the way back, no cats, and 24" glasspacks... Loud as hell and lots of power... You've got to let the engine breath or you won't be able to have any power... The freer flowing the exhaust, the less the engine has to work to remove the exhaust gasses from the pipes... Less work = more power available...