Am i asking too much of my 4.0? lack of power

I feel your pain man. I was in the purple late model XJ you guys PASSED in the Mesquite, NV area on the 15 headed to Moab. I was loaded down like crazy had at least 4-500lbs of crap stuffed in, plus all the offroad stuff. I sturggled to keep 70 on anything but flat road or down hill. My heep heats up a little more then i would like on the up hills also so im pretty much in the same situation you are. Gunna check the cat. And start budgeting for a stroker.
 
rmz45099 said:
I feel your pain man. I was in the purple late model XJ you guys PASSED in the Mesquite, NV area on the 15 headed to Moab. I was loaded down like crazy had at least 4-500lbs of crap stuffed in, plus all the offroad stuff. I sturggled to keep 70 on anything but flat road or down hill. My heep heats up a little more then i would like on the up hills also so im pretty much in the same situation you are. Gunna check the cat. And start budgeting for a stroker.
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No way! i remember your XJ, thing looked pretty well set up. On the radios we kept having to say "the nice XJ thats not in our group" haha. I think i also saw your XJ in some parking lots in Moab, city market maybe? Either way thats pretty cool that you found this place and this thread.
 
Haha ya thanks for the compliments. Kept saying to my GF, "Here comes another one" refering to your group. Saw you guys a few times also, but was never in a position to stop and say hi. Was there with only one rig so it would have been nice to be able to tag along on some trails. Still had a great time, was just a little more conservative with offroad driving. Good to see you guys made it back.
Id say go with 4.56 also i have them and can't even think what it would be like with less gear.
 
Interesting discussion so far.

For the OP, is this happening only when you are loaded up for camping, w/ the tent?

I had similar "symptoms" with my first XJ, in the hills of PA w/ a canoe on top of a roof rack. Plus 2 people w/ gear for 3 days on a river. Luckily, that trip wasn't the time it threw a rod (that was after a trip that got it hydro-locked) going up the highway in PA. But, that trip with the canoe really sucked on throttle response and MPG.

If it occurs mostly with your camping setup, I would suggest trying to make your setup a little more aerodynamic. Looking back at the original picture, I would buy a big tarp to put over the whole mess when you are on the highway. That should clean up the air flow enough to help.

That would be a cheap investment to try before getting new gears. Should help regardless of the gears.

My thinking is that if you were hauling a smooth box of the same weight, you would probably be doing better. But you're literally carrying a big messy parachute on your back end. When I had a spare tire on my roof rack, it was a 1-2 mpg drop. The canoe took it down a good 8-10 mpg.

cheapcherokee93 said:
Looks like the consensus is definitely that my engine is being normal. I guess thats good, although a little disappointing because i dont like going slow :rof: good to know im not the only one crawling over grades at 4,000+ rpms

i guess now that i think about it, 5,000 lbs and a parachute of a tent strapped to the back is not a good recipe for speed on a vehicle with sub 200 hp, 33s, and inadequate gearing. :gee:
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Keith_Indy said:
Interesting discussion so far.

For the OP, is this happening only when you are loaded up for camping, w/ the tent?

I had similar "symptoms" with my first XJ, in the hills of PA w/ a canoe on top of a roof rack. Plus 2 people w/ gear for 3 days on a river. Luckily, that trip wasn't the time it threw a rod (that was after a trip that got it hydro-locked) going up the highway in PA. But, that trip with the canoe really sucked on throttle response and MPG.

If it occurs mostly with your camping setup, I would suggest trying to make your setup a little more aerodynamic. Looking back at the original picture, I would buy a big tarp to put over the whole mess when you are on the highway. That should clean up the air flow enough to help.

That would be a cheap investment to try before getting new gears. Should help regardless of the gears.

My thinking is that if you were hauling a smooth box of the same weight, you would probably be doing better. But you're literally carrying a big messy parachute on your back end. When I had a spare tire on my roof rack, it was a 1-2 mpg drop. The canoe took it down a good 8-10 mpg.
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I definitely see what you are saying, the tent alone does play a huge part in the restriction. on 33s ive driven it:
no tent, loaded
tent on, empty
no tent, no load
tent on, loaded (on multiple occasions, not just this one)


with the tent on and no load, I got caught in some wind heading up to Cleghorn and it slowed me down significantly. could not hold over drive on level highway, so i just cruised 55 mph in 3rd since the wind was pushing me around left and right.

ive also had the tent on and loaded down and was able to hold OD just fine, but it was less weight and level highway for the most part (and no wind!).

i think we can draw the conclusion that the tent in its current mounting is a severe hindrance. The reasoning for it being mounted so high was so i can stand up my 33" spare tire in the bed. with it laying down its an awkward shape and takes up too much space. i built the rack for the tent as low as i could while clearing the tire.

and i like your tarp idea. might have to try out something like that. would also be cool if i could get the tarp to wrap around the tent rack, and function like a soft camper shell.

on another note, i wonder if putting a wind deflector in front of the tent would help at all? you know, to make the air go over the tent smoother?
 
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cheapcherokee93 said:
and i like your tarp idea. might have to try out something like that. would also be cool if i could get the tarp to wrap around the tent rack, and function like a soft camper shell.

on another note, i wonder if putting a wind deflector in front of the tent would help at all? you know, to make the air go over the tent smoother?
Click to expand...

I think it's more wind from the side that's catching it then the stuff at the cabtop/ten interface.

That's one reason I don't think it effects XJs as much as MJ's, but it's also very condition specific (lot's o' variables.) When you need to pinch pennies, it's best to log what changes between trips. Tire pressure, load, road conditions.
 
Just a side note not related to power but a suddestion. I would recommend fabbing up a removable wind deflector like they have on bike racks. I bet that would help with the headwinds while hauling the tent up top. I've had some really good results using them in several different application.
 
did you pop the exhaust off to check the cat yet?
 
yup. probably not very different from my 62 ford with a 223.

p003245.jpg
 
cheapcherokee93 said:
negative. been busy with other things lately, and admittedly have turned more attention to my 63 falcon project

Click to expand...

Nice car, Matt. A buddy of mine at work also just picked up a 63 Falcon. But his is a 4-door.
 
Well an update on this. cut out the cat and found no restriction in there, everything is clear. Just for fun i drove it around with the cat cut out and i felt absolutely no power differences. My jeep is just that slow. For now i will just live with going slow, in the mean time i will be exploring/researching what i'm gonna do about it. I want to do gears but more HP also sounds appealing :rof:
 
I'm in the same situation. More load though, Jeep curb weight is ~4100 lbs and my big tent trailer is ~2700 lbs unloaded. 4.56, automatic and 265/75-16 tires.

Long tall grades make it scream and slows down quite a bit (I do the recommended run in 3rd when not on flat ground). I can tow in OD on level ground with no issues though.

I'm near sea level though.

I bought exhaust and intake stuff but haven't gotten around to installing it yet.

Without the trailer the Jeep drives fine though.
 
Do a wet/dry compression test. That will tell you a ton about the condition of your engine.
 
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