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Discussion Starter #1
So when I go uphill at times I'll lose power I have a 2.5 6" lift with 35s I know I won't have a lot of power but I shouldn't lose as much as I do, I'm guessing it's the fuel pump... also at times when I start it it'll take a while.. any thoughts?
 

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Don't guess. Get a FSM and troubleshoot the problem. If you suspect the fuel pump, check the fuel pressure. If it's not to spec, it could be the pump, or regulator or a plugged filter.
Arbitrarily swapping parts is an expensive way to troubleshoot issues.
 

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So when I go uphill at times I'll lose power I have a 2.5 6" lift with 35s I know I won't have a lot of power but I shouldn't lose as much as I do, I'm guessing it's the fuel pump... also at times when I start it it'll take a while.. any thoughts?
The 2.5 with stock tires and gearing is the minimum put out by Jeep. Although on the trail the 2.5 will perform adequately, on the highway it leaves a lot to be desired. It becomes a dog on the road when you go to 31" tires. With 35s the problem is magnified.
Your stock gearing is probably 4:10, but don't worry, with the 35s it probably won't last as long as with stock sized tires. Then you can go to a Ford 8.8 with 4:56 gearing or some other axle with 4:88 gearing. Time to do a little homework.
Don't forget to match the front axle gears to the rear, or you will be looking for a transfer case.
For more power, you might consider dropping down to 31s.

If you truly believe you have an engine problem, see the post by Airslot.

Don't guess. Get a FSM and troubleshoot the problem. If you suspect the fuel pump, check the fuel pressure. If it's not to spec, it could be the pump, or regulator or a plugged filter.
Arbitrarily swapping parts is an expensive way to troubleshoot issues.
Boy, Howdy!! I preach this continually.

MudmagnetYJ has a name for just throwing parts at a problem without proper diagnosis. I don't remember exactly what the name is, but he hits the hammer on the nail.

Palafoxyj, check out a post by MudMagnetYJ and look in his signature. The last thing is a link to "Service manuals". Click on that link and find the Factory Service Manual for your year Jeep.
Find the diagnosis section for 2.5 motors. Any money you spend on diagnostic tools will save you that much and more by not replacing perfectly good parts.
By the way, you'll save a lot of time too. And frustration. The Lord will be happy because you won't be cursing.
There's a lot to be said for proper diagnostics.

Good Luck, L.M.
 
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Discussion Starter #6
Thank you guys for the info! New to the jeep life but I will definitely get some help from my trusted mechanic and I won't replace anything if it's not the issue.. what do you mean by swaptronics?
 

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Discussion Starter #8
Cool thanks you guys! It sucks because where I'm from there's no trails really and the jeep community is pretty small
 

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So when I go uphill at times I'll lose power I have a 2.5 6" lift with 35s I know I won't have a lot of power but I shouldn't lose as much as I do, I'm guessing it's the fuel pump... also at times when I start it it'll take a while.. any thoughts?
Just pointing out that this is another one of those "seat of the pants" diagnostics that can get you into trouble, especially if you have a new (to you) Jeep and don't have any performance baseline to compare it to.

You say you shouldn't lose as much power...compared to what? Was the Jeep driving fine for a while and then started losing power in certain situations? Or do you feel it's just underpowered going uphill because that's just your opinion? The Jeep may actually be fine mechanically, it's just hobbled by a stock 2.5 trying to turn 35s.
 

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You're going to be chasing Bigfoot on this one. What's your gear ratio? For 6" lift on 35s with a 2.5L, you could have lots of hidden issues.

I suspect your axles were not geared properly. Factory your ratio should be 4.10. To match the factory gear setup with 35s, you want 4.88s. That's what I'm running.
 

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You need deeper gears as mention above. Go for 4.88 or 5.13.
Time for OP do his homework. Some axles won't accept the deeper gears and others require machine work to accept 4:88s and 5:13s.
How about some kind of locker at the same time.

Depending on how OP intends to use the Jeep, he may find it's way less expensive to go to a 2 1/2" lift with 30" or 31" tires.

Good Luck, L.M.
 
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