Towing ?

William Johnson

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Reading some threads it sounds like the 7.3 NA idi wont tow for beans. Is this true ? If so, what were they made to do.
I've got my first diesel, 1990 4x4 7.3 NA extra cab long bed Auto E4od. It runs and starts great and was hoping to tow a trailer ( not full time ) just get it down south to park it in good weather. Oregon to Arizona towing 30ft toy hauler at 6400 pounds. I wouldn't be nervous but some threads on here make me that way. Opinions and advice I'm open too !! This site rocks, I'm constantly learning something
 

Clb

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All the downhill bits will rock, the hills it will climb over at reduced speed.
Na aint no power tow pig, but it will pull (in 2nd or 3rd) not 4-5 th...
 

Farmer Rock

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These trucks in their stock configuration,will pull anything you put behind it,just not as fast as the new trucks.You have to realize that these IDIs were made when the national speed limit was 55mph which they will run absolutely no problem with a load on the highway...6400 pounds is nothing for an IDI,but it's all about how you drive it..Don't lug the motor down while pulling a hill,be sure and keep the rpm's nice and high.The only reason these trucks get a bad rap for towing,is because that's coming from guy's who drive new turbo diesels,and want to be able to do 70-75mph fully loaded which is nuts.The main selling point on the new 6.7 psd was that you could tow 35k pounds and maintain a steady speed of 75mph up hill:bail:idiot:You would have to be really stupid to actually do that,and don't get me wrong,those trucks are very impressive,but I definetly wouldn't buy one with all the junk under the hood,and I sure wouldn't be towing 35k with any pickup truck...You shouldn't have any problems towing that with your truck,as long as everything is in working order,and you have good trailer brakes.

Rock
 

Clb

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Good write up ^^^

But I won't concur with the 70 mph bit....

Just for grins I remember a class 8 tractor being ticketed on I 80 mid west section doing +110, before the ntl. 55 farce was put in place!
Go joogle it
 

Kevin 007

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Yes. They will pull, but slow on hills. With your E4Od, don't expect to pull any significant grades in OD, be proactive and downshift early and keep the rev's up for hills. As mentioned above, a pyrometer is a must if you want the truck to last. And with your E40d, add a nice big trans cooler.

Find out what gear ratio you have. 4.10 ratio does considerably better then 3.54's when towing.
 

Greenie

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I've towed a 3 ton travel trailer across the US 3 times and across the Sierra Madre (Maine to Mazatlan, Mexico) eight times. It will do 80mph unless there's a headwind or a grade. I often did tow well over the speed limit - even as the speed limit increased from the national 55mph to 75mph (in some states). I've never had an accident towing at speed and the truck I bought new in 1993 has had one transmission rebuild, one water pump, one injection pump, one set of injectors, a bunch of U-Joints, 7 sets of tires, and 5 pairs of batteries in the 270K miles I've owned the truck.
 

lotzagoodstuff

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I would concur with almost all above. Get a pyrometer, get it timed correctly, make sure you have a good fuel filter in it, pay attention to the grades and altitude, and don’t be afraid to run it against the governor as you pull the grades. Be prepared to have the skinny pedal at the floor and see 35 mph with your hazards on until you crest the passes, but you’ll get there eventually. One thing people overlook is the thinner air really hurts the normally aspirated IDIs ability to make power. When you look at dyno testing, they always give you an altitude corrected number, because thinner air directly hurts performance. A turbo charger helps fight that. I don’t feel like my normally aspirated 93 towed that bad compared to my PSD in flat terrain, but in the hills it’s night and day different.

For what it’s worth: I’d be more worried about the transmission stranding you than the normally aspirated engine. The pre-1994 E4ODs have several known weak points, and if you’re hasn’t been updated/overhauled, I would at the very least have a trans shop measure pump pressure. If you don’t have a transmission cooler, I’d install one for sure.

Good luck on your journey to sunshine
 

Kevin 007

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Yup. And we hear a lot of horror stories about the E40d's, but I along with many others have had great luck with them; including the early ones and including towing; provided that you don't abuse them, keep the fluid clean (I use synthetic in them), be proactive in downshifting manually before the hill (get off the throttle a tad for the shift). As I said above, the 4.10's are a big advantage for you over 3.54's. With 4.10's you will be able to pull heavy loads in OD on the flat-ish areas, whereas that's sometimes pushing it with 3.54's
 

ih8minimumwage

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NA IDI will pull a house down, it just won't be quick to do it. Max I pulled was about 15k (Gehl RS5 forklift on a Towmaster trailer) and that was slow going with trailer brakes saving the day.

Just be ready to ride with the real trucks on the grades with the flashers going.
 

Cubey

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Just be ready to ride with the real trucks on the grades with the flashers going.

I have to do that with turbo and 4.10 in my RV. Doesn't matter to me. What's an extra 2-3 minutes? I liked my 3 cyl/3 speed AT Geo Metro even though that was about as fast as a towing NA IDI. I was in the truck lane crossing mountains in it.
 

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