Alright guys, I'm happy to have found this site since I can't find any info from the local Ford dealerships. I have a 1988 e150 with a 302 and the 4 speed auto trans. Rear gear is a 3.55. I bought a 1965 layton camper that I want to take on vacation in 4 weeks. The problem is the van struggles to get over 50 mph. The van is tuned properly and moves its own weight just fine but the camper is about 2300 lbs. I read that changing the ratio to a 3.73 would give me more pulling power... Is this true? I'm not concerned with losing a little gas mileage either. Would a 4.10 gear be driveable on the freeway at 65? Any other ideas would help! I have stock 15" tires as well

 

The van struggles with the camper attached, no problems when its driving by itself

 

Are you towing in OD? Try using 3 instead, save OD for when towing downhill with the wind at your back. In OD below about 60 mph your rpm is too low to make much power. If your a/c is on, that only makes it worse.

 

I'm Def not using over drive. The van won't even shift into 4th when pulling the camper, and no A/c either.. thanks for the reply though.

 

OK , but your passing gear does work? Not sure if your '88 has a throttle valve rod or a cable, but the trans throttle valve cable on the later ones, has a nasty habit of breaking the plastic end that attaches to the throttle body. If that happens you'll have early up-shifts and no passing gear.

 

Have used E150 w/302, AOD & 3.55 to pull trailer w/2800 lb car on it up & down East coast, going w/traffic w/o issue anywhere except the steepest sections of interstate. And it mostly ran in overdrive, only shifting down on grades & stronger head winds.

You say "The van is tuned properly" which may hint that it recently wasn't? My guess is that performance is compromised. If it was out of tune so as to run rich it may have ruined catalytic converter, restricting exhaust?

Or could be in tune, but have brake dragging? Or have throttle cable out of adjustment? Be sure when pedal is to the metal that throttle is wide open.
Once suffered loss of power & found floor mat pushed up under gas pedal, blocking full travel!

 

I would have to agree with this ^^^^^. As much as I do not respect a 302's towing ability, not being able to attain highway speeds with a 2300 lb load is not one of its many drawbacks. Your rig feels like it is running ok without the load, but it isn't. Fuel filter, exhaust constriction, fuel pump, out of tune or something. But, it does not need mods to tow that small load. Something is wrong.

Oh, hold the phone. does that rig have a catalytic converter? That would be your problem. Packed with crappola if it has one. Best course is to remove entirely, or cut doors in the bottom, knock the crappola out on the ground and weld it back up.

 

well, with this van, I actually have 3 cats on it, one on each side of the Y pipe, and one just before the muffler. tomorrow I will be hollowing out all three then sewing them back up.. I too thought this thing should be able to haul a small camper like that .. ill check back in afterwards, thanks so far!

 

Whoa Big Fella!!!!

Have somebody w/experience check out those "3 cats" before you destory them.

 

Well, you can't fix them, that is true. But, you can make them less malicious that is for sure. And, unless you believe in the tooth fairy, or you have found a place to buy leaded gas, they are not doing anything good for Mother Earth.

I'd be pretty comfortable to hollow out any of the catalytic converters in line AFTER the O2 sensor. I think I'd do those first if there one is before the O2 sensor.

 

If a catalytic converter gets clogged it's usually either by melting down inside from extended running over rich mixture, or from collisions that break up the matrix inside, that may leave dent. There's no foreign debris. Feds say you can only replace it.

If you find a clogged converter "Packed with crappola" it often means the motor is blowing excess oil out the exhaust. Usually a sign of problems w/motor commonly linked to poor performance. Low compression, worn rings, blow by, valve seals. Converters contaminated like this can burn themselves clean again, after motor is fixed, eliminating oil in exhaust.

 

Oh, there are a lot of things that cause these gizmos to get clogged. My 454 K2500 Burb had one that was nearly solid inside. I opened it up and all manner of crappola fell out onto the ground. Just report back when you have tested the theory and we will see. My money is on the crapalytic converter.

 

thanks everyone so far, I'm going to cut them open either tomorrow or Tuesday. it did have a problem with a rich mixture when I bought it, rats built a nest near the ecm and ate the wire that lee to the o2 sensor. fixed that after a while but gas performance was terrible so I hired a Ford mechanic who found the issue. I will report back after surgery.

 

Well to day it was 100 degrees here in detroit MI and I was under my van! I cut the first converter open and hammered the cone out of the converter, to my surprise, it was white and clean, not a single particle of anything. After being under there, the van has two converters not three. There both after the O2 senser. One is located at the Y and the other just two feet away down stream. Now if the first one was so clean, would that mean that the other should be clean as well? I didn't open the second one because its was a lot of work to clean out the first one... the welder kept over heating and shutting down too So with that note, what does this forum suggest I could try next to help with my poor power under load?? Could ignition timing being to far retarded cause this? I checked the plugs just a month ago and replaced the wires cap and rotor.. replaced the fuel filter in the rail and it has two pumps, one in each tank which both work evenly so I'm ruling out fuel problems.. ???????

 

You may be blaming the wrong vehicle, I tow with an 89, 302, AOD trans and here in WV its up hill both ways. I don't tow fast but a car trailer with another E-150 and a 10% grade I do about 30 mph so your camper shouldn't hinder you at all. One thing that caused me to have the exact same trouble you described on my last trip to SC was the lining on my brake shoe came loose and spun over the other shoe, it was pulling terrible and I was empty. It wasn't until I stop for gas and on my walk around found one wheel really hot that I found the trouble. You may want to give your trailer a good going over, brakes and bearings, especially since you said it runs fine when not towing.