4x4 e350 w/7.3 towing 8500lbs possible

[toytime]

Hi guys, I just picked up an E350 with the 7.3, and a ujoint offroad 4x4 conversion. Its a 2003 extended 15 pass van with 410 gears and 35 inch tires, and edge evo cs programmer. I am running the programmer on stage 1 so I can keep an eye on the egt. (alarm set for 1250). stock exhaust, KN high flow air filters. Anyway it seems ok for power but when i hooked up my 24ft toy hauler (weighs about 8500), i had trouble hitting 60mph on the flats and egt was always creeping up. I have seen the power of the 7.3 in buddies trucks and I know it should not have a problem. Has anyone else towed a trailer with a 4x4, 7.3 van? I have not done a lot of work on this yet but before I start spending money I want to know if I am even on the right page. I assume it should not have a problem. I have read the e350 is different than the f350 7.3 without intercooler and lower hp rating but is that the reason it wont tow?
thanks

[04 E350 Van]

This won't help you but...
I have a E350 extented w/ a 6.0, total stock, which used to have a GVW of over 10k lbs and pulled a enclosed motorcycle trailer with a grand total of 3300#.
Could easily pull it at 65-75mph over flat interstates... 50-60 up hills and still got 14mpg
I have since unloaded the weight in the van and gets alittle better mpg, 16 hauling the trailer

[hogasm]

My 97 E350 has pulled a 12k 32' bot behind it for over 200k miles with no troubles. No tuner, only mod is K&N filters in the stock box.
Van has 553k on her and probably has another 200k pulling a 10k ditch witch.
It won't break any land speed records but will tow 65mph comfortable

[toytime]

thanks for the feed back thus far. Any idea what your 7.3 would rev at when about 60 mph. mine is about 1900 to 2000. Thanks

[hogasm]

Don't have a tach

[Breaking]

I Just picked up my 7.3 as well with plans to tow my 24' enclosed toy hauler at about the same weight as yours. I

I have not hooked it up yet to my trailer but it feels very sluggish and almost like its rarely in boost. It has an edge ez hooked up at stage 4 (60hp 100tq) Im really hoping it will do 70mph safely.

From the research I have been doing It sounds like I need to check the screen going into the FPR as they commonly get very clogged and rob power and fuel economy.

[toytime]

yeah, my boost gauge reads 2 to 3 then sometime will get up to 5. I assume it should be higher? I would be interested to hear if the fpr clean makes a difference, and what yours tows like with the trailer behind it. thanx