[yamaniac]

Hi Guys,

I recently got my 2wd mm540 to a 4wd, although everything is running smoothly, there is a huge drop in mileage and has become a cause for concern. But it is a very capable off-roader, but the mileage stinks!

Before in the 2wd I used to get somewhere around 12-13 Kmpl. But now after the conversion to a 4wd. I don't think its giving me even 8kmpl roughly!

I spoke to my mechanic and he insisted that we get the diesel pump serviced, But even after so, the problem is still the same!

My thoughts are, is there something that has to do with the crown pinion ratio? It has the original 540 diffs and crown pinons.

I am aware that the The Tcase and the front differential will add another 70+ Kilo weight on the jeep.. But I dont think that would make a huge difference though? or does it?

I haven't installed lamda though! will this help?

Any thoughts on this gurus?

[ex670c]

Originally Posted by yamaniac

Hi Guys,

I recently got my 2wd mm540 to a 4wd, although everything is running smoothly, there is a huge drop in mileage and has become a cause for concern. But it is a very capable off-roader, but the mileage stinks!

Before in the 2wd I used to get somewhere around 12-13 Kmpl. But now after the conversion to a 4wd. I don't think its giving me even 8kmpl roughly!

I spoke to my mechanic and he insisted that we get the diesel pump serviced, But even after so, the problem is still the same!

My thoughts are, is there something that has to do with the crown pinion ratio? It has the original 540 diffs and crown pinons.

I am aware that the The Tcase and the front differential will add another 70+ Kilo weight on the jeep.. But I dont think that would make a huge difference though? or does it?

I haven't installed lamda though! will this help?

Any thoughts on this gurus?

Hi Yamaniac,

Please check the following

1) Front & Rear Brakes are binding.

2) Change the Front Axle Flange to Free Wheeling Hub.

3) Check the Front & Rear Differential Ratio

4) Rear Prop Shaft Alignment

Regards,

Arka

PS - Post a few pics of the front and rear Diff, under the chassis.

[shankar.balan]

With the added 4WD you should experience a drop of about 2Kmpl more or less, on account of the increased weight and the fiddly bits added in.
More than that is strange.

[dhanushs]

Originally Posted by yamaniac

But now after the conversion to a 4wd. I don't think its giving me even 8kmpl roughly!

In my limited knowledge:

Get a free wheeling hub. It frees the front axle and differential, and should get you back the 2WD mileage.

Also, have you retained the left aligned rear differential?. If so, I guess with a T-18 TC, (IIRC, you got that?) The prop shaft will be angled and be far from efficient.

So, please get a right aligned rear differential (If not done).

Other than that, unless the work is shoddily done, I dont see a reason for the drop in mileage.

I haven't installed lamda though! will this help?

Yes, please..

[Sutripta]

Hi,
Simple things first. Is the speedo/ odo showing correct readings?

Regards
Sutripta

[HJ13]

Hi yamaniac,

I observed 2 to 3 Kmpl of drop in mileage after 4WD conversion.
I have FWH installed.

HJ13

[AVR]

I did Ahmedabad-Lonavala-EXAMM-Karjat-Ahmedabad in 2010 with my DP-engined 540 and I got an average of 13.5 for the entire trip which included expressways (lol in a jeep!) and offroad (jungle slush trails). And my Jeep is 4wd with FWH!

Freewheeling hubs is the way to go! Fix them up and then see if you still don't see reasonable performance improvement then it can be other things.

Cheers,
Adi

[yamaniac]

Thanks alot for the input guys!

Hi Arka,

I Will post a few pics soon, I am currently in the UK right now on some work, will post it by the end of this week. Thank you so much!

Originally Posted by ex670c

Hi Yamaniac...

...under the chassis.

Originally Posted by shankar.balan

With the added 4WD you should experience a drop of about 2Kmpl more or less, on account of the increased weight and the fiddly bits added in.
More than that is strange.

Originally Posted by dhanushs

In my limited knowledge...

...I dont see a reason for the drop in mileage.
Yes, please..

Originally Posted by Sutripta

Hi,
Simple things first. Is the speedo/ odo showing correct readings?

Regards
Sutripta

Originally Posted by HJ13

Hi yamaniac,

I observed 2 to 3 Kmpl of drop in mileage after 4WD conversion.
I have FWH installed.

HJ13

Originally Posted by AVR

I did Ahmedabad-Lonavala...

...Cheers,
Adi