Is there any mods that can increase low down torque for when I am towing 1ton +.
Compared to a manual diesel the 4.0L is not that good especially with fuel economy, here in the UK it is breaking me running the 4.0L.
I could get rid of it and get another car or a diesel XJ but the Euro engine was pants really, lots of head problems etc...
Anyway I like my car and know what work and money I have done on it, it also has NO rust.
Is there a cam designed to give better grunt or has anyone fitted a Turbo to these, I know you yanks all love a blower but here everything is turbo'd especially diesels.
Not sure how it would affect the auto box and changing gear! I am thinking of just a small one so as not to grenade the engine.

 

with towing that much..you need to consider more than just motor

the trans will need a cooler for sure
gears should be changed....3.55 to maybe a 3.91 or 4.11
leaf springs in the back are going to need to be stiffened up a bit (which will make for a very bumpy ride when your not towing

also the load range on the tires....your tires are designed for the weight of the jeep...you may need to upgrade to a heavier ply tire to make

reality....cherokees were not meant to tow alot...you might be better finding a dedicated tow rig...(old truck or something)

Its possible to do it with a jeep...i just think you would be better off finding a tow rig and keeping your jeep the way it is

i might be wrong...someone else will comment and see what they say

 

I would regear and get a trans cooler.

Solves it all.

 

Gee Oh Dee nailed it, gears and additional cooling for the trans. The gears will cost you a bit in fuel economy though. The trans cooling is not an option, you'll be blowing fluid out the dipstick without it.
Since you asked about a turbo:
http://www.505performance.com/Our_Turbo_System.html
http://www.shop.505performance.com/p...&categoryId=15

Of course it's going to cost you $4 grand US and if your cooling system is already marginal... well..

 

To get specific, OP mentioned towing ~one ton. A ton being 2k lbs, well within the limits of the XJ (500/5000 lb. load limit) however, I agree with the fact that XJ's just don't make the best tow rigs, but that doesn't mean going any getting a specific tow rig for more money than say, a tranny cooler (I think Gee already said that..) and as you said, rear leafs will probably suffer unless beefed up some. Other than that, knowledge of how to drive with a trailer can have a big impact as well. Slow starts and gentle stops will save tons of wear and tear. Also, I saw someone post a couple weeks ago about towing in 4wd to save stress. This is kinda backwards. While it will help alleviate the rear from doing all of the work, it's putting undue stress on the front end components.

 

1 ton is not much at all! 2200lbs! . Mine has the factory tow package which includes trans cooler and my rear springs are new, they hardly move when I add my trailer or boat.
This is not the issue, its low down torque the XJ lacks when towing, especially for stop starts and hills. Its great once it's moving on the motorway and fuel economy is not too bad really. But on hills it struggles.
Just wondered if someone in the US had a cam to provide better torque or as I stated a small Turbo.

I have been looking at the 2.8CRD Cherokee (Liberty) KJ manual.
These have huge torque and power but also diesel fuel economy.
I don't think they are available as a diesel in the US.

http://www.autotrader.co.uk/classifi...01218468491479

 

just a thought- might be worth your time searching the junkyard for axles from a 2.5L that came stock with the 4.10's. prolly cheaper than regearing, esp if you'd have to pay someone to do it.

 

Might consider trailer brakes, too. That'll keep your brakes lasting longer.

 

Although I am generally happy with my Jeep for towing, I would also like to add a little more power. I usually tow a vehicle with mine (so 1.5-2 tonne normally - that's 3300-4400lbs). Well within the 3.25 tonne (7165lb) towing limit here in the UK for a 4.0 XJ.

I too am in the UK, but I run it on LPG/Propane, which makes the MPG less of a problem. Whilst towing on a run I get 15-18mpg UK (18-22mpg US), but as LPG is half the price, this equals a diesel doing almost double those figures - which ain't bad.

The option I'm currently considering is increasing the compression ratio (CR). LPG has a higher octane rating, so can run much higher CR's - even up to 15:1, although most would NOT suggest going over 12:1 from what I've read. So with the CR increased to something around 10 or 12:1, the engine all freshened (valves reseated, new rings etc), this should nett me some extra grunt. I've got lots of maths still to do on this though - including the price of engine parts.

Totally open to ideas for extra grunt too.

I'll check to see what gears I have in mine. But I know it revs low at highway speeds.

 

Hell i thought if you even roller blade they tax you for putting the wheeles on the road. Good luck and bric thosewindows up.

 

Will the HG and head bolts take that high of compression?

Also, I'm pretty sure all the 505 performance turbo kits are for Wranglers only. I could be wrong tho.

 

They've added them for XJ's now too. Gotta relocate the battery and AC compressor. Must've found some way to finagle it under the hood finally.

 

Here's a fun thread about turbos on 4.0s: https://www.cherokeeforum.com/f67/tu...d-4-0l-150903/

I'd also recommend grabbing some deeper gears for towing. The "towing package" on older XJs used to include 3.73:1s where regular autos came with 3.55:1

If you want a diesel check out an OM617 swap: http://www.mercedesdiesel4x4.com/ the AW4 might be a hassle though... so ditch the slushbox and grab a stick