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harryw
16th March 2008, 09:08 PM
I have just changed my Avan Cruiseliner for an Avan Euro Star which is a much more traditional shaped caravan.

With the Cruiseliner at at steady 90kph using cruise control I would return around 11-12 L per 100km in my 02 TD5 Disco.

On our first trip this weekend we returned about 17-18 L per 100km this time sitting on 80kph with the tacho hovering around the 2250 to 2500rpm on the level.

It was not windy and the return trip to Cervantes is not hilly at all.

Is this this sort of return I should get and if so is there anything I can consider doing to improve it?

regards

Slunnie
16th March 2008, 10:18 PM
It sounds like the torque converter wasn't remaining locked up. The lockup speed is 80km/h, so as you good above and below that speed it will lock and unlock. At 90km/h it will remain locked. That economy doesn't surprise me with an unlocked torque converter based on what I've done while towing a car trailer with a torque converter that wouldn't lock.

harryw
17th March 2008, 10:19 AM
Thanks for that.

This may be a dumb question but does this mean either

1. The torque converter only locks at above 80kph so to achieve better fuel consumption I should drive faster, say 85-90kph, or

2. I have a problem with the torque converter not locking up and it should be fixed at the next service which is scheduled for 3weeks time?



regards

harlie
17th March 2008, 10:43 AM
A 1 - yes >85 will keep it locked
A 2 - possible but unlikly. to check put it in 3rd - converter should lockin over 70 in 3rd

My experience is that the small diesels will drink fuel towing.....

Mikems
17th March 2008, 10:45 AM
I have a Avan cruiser I tow with a D1 TDi. I get about 11.5 lts/100ks with the cruise control. I generally travel about 10ks under the speed limit. This means I don't have to overtake too often & others travelling at the speed limit can pass. If I'm not travelling above 80ks I put it in 3rd. This stops the torque converter slipping. I would imagine your new van is heavier & a bit more wind resistance.
Michael.

Pedro_The_Swift
17th March 2008, 10:58 AM
Very Nice:D

I'd be inclined to try 90 again,,

Wheres max torque on a TD5?



https://www.aulro.com/afvb/

harryw
17th March 2008, 11:00 AM
Mikems

The TARE is 1700 compared to 1400 on the Cruiseliner and yes it is much larger so a drop in consumption was to be expected.

I wouldn't have thought of dropping back to 3 at around 80 as I would have though the engine would have been working a lot harder.

Up to now the fuel was courtesy of a company fuel card but now as I am about to retire and pull the van around OZ the fuel usage has a more significant impact on the pocket:).

I guess the next lot of test runs will be done @ 90kph in D and 80kph in 3 to see which fares the best.

Many thanks to you Slunnie and harlie for your helpfull answers.


(this is what makes this site sooooooooo good) :D:arms::arms::arms:

best regards

harryw
17th March 2008, 11:15 AM
Pedro

Ours is 4 years old but in immaculate condition and we absolutely love it and as we are going to spend 5 months up in Broome before starting extended trips we needed more space.

We were sad to see the Cruiseliner go after 9 years but there is a big difference in using it for weekends and 2 week holiday trips compared to 5 months straight.

The sad thing having been in the WA Avan club since 1997 we are no longer eligible for membership because we don't have a "pointy" van, but those are the rules and we have to accept that.

We are going to the annual convention in Busselton next month as guests so we will be leaving on a high note in a gathering of around 230 pointy AVans.

regards

Redback
17th March 2008, 11:59 AM
Very Nice:D

I'd be inclined to try 90 again,,

Wheres max torque on a TD5?



http://www.productreview.com.au/uploads/images/items/75123_avan_euro_star.jpg

Starts at 1950 RPM Pedro.

Pedro_The_Swift
17th March 2008, 12:07 PM
hmm, does it reach peak torque before converter lock-up in top?

Redback
17th March 2008, 12:15 PM
Starts at 1950 RPM Pedro.


hmm, does it reach peak torque before converter lock-up in top?

Dunno i have a manual, but i would assume so, 90kph on my manual is around 2000rpm with 32s in 5th, this is normally when i go back to 4th when the revs drop this far.

I think 100kph is a better touring speed.

Baz.

BigJon
17th March 2008, 12:15 PM
If the van pictured is similar to yours, my strong recommendation is tow in third (auto trans). Towing in overdrive is a sure way to book a trans rebuild into your future ($3000 ++).

BigJon
17th March 2008, 12:17 PM
I can't edit my post for some reason, but I will add that with a manual transmission and a van that size, use 4th for towing.

Pedro_The_Swift
17th March 2008, 12:20 PM
If the van pictured is similar to yours, my strong recommendation is tow in third (auto trans). Towing in overdrive is a sure way to book a trans rebuild into your future ($3000 ++).

Thanks for that BigJon;)
what do we need to do to make towing in top viable?
better cooler? better fluid?


Thanks Redback,, thats what I was trying to get at,,
I think-- at peak torque the car should be at its most economical,,
am open to actual knowledge here!!!

Redback
17th March 2008, 02:04 PM
Thanks for that BigJon;)
what do we need to do to make towing in top viable?
better cooler? better fluid?


Thanks Redback,, thats what I was trying to get at,,
I think-- at peak torque the car should be at its most economical,,
am open to actual knowledge here!!!

An extra oil cooler is a must on the auto when towing and premium oil and regular oil changes too.

I tow in 5th all the time, with no probs, some may know of my gearbox woes just recently, turned out that 5th gear was in perfect nick when the box was checked.

Can't speak about autos and towing heavy loads in overdrive.

Baz.

BigJon
17th March 2008, 03:24 PM
I tow in 5th all the time, with no probs, some may know of my gearbox woes just recently, turned out that 5th gear was in perfect nick when the box was checked.

.

Until it breaks...

We had to replace a Defender gearbox when 5th gear pretty much exploded. Towing a tandem box trailer with canvas covered frame. 120 000km on the clock.

BigJon
17th March 2008, 03:28 PM
Thanks for that BigJon;)
what do we need to do to make towing in top viable?
better cooler? better fluid?



The cooler would be the most important thing, but I still wouldn't be confident.
It only takes a little bit of slippage in the clutch packs to generate a lot of heat, which will kill the transmission in very short order.
I have seen them with the plastic breather pipes melted clean off! :eek:

The engines have plenty of grunt to pull the overdrive gears, but I still wouldn't do it.

I tow my tandem box trailer behind my Rangie in 5th, but I don't change into 5th until 100 kph, and I down change for any hills, overtaking, etc.

matbor
17th March 2008, 03:29 PM
Until it breaks...

We had to replace a Defender gearbox when 5th gear pretty much exploded. Towing a tandem box trailer with canvas covered frame. 120 000km on the clock.

Was that towing the trailer for all of the 120,000km's or just 1% of it ?

LandyAndy
17th March 2008, 08:11 PM
Hi Harry
The lower gear/work harder is somewhat of a myth.
In 3rd its likely doing the job easy at higher revs than really strugling in 4th.
When doing it easy at higher revs it will use less fuel than 4th whilst pulling hard.
Use the 4th downhill/flats with no headwind,and makesure its not under load as it will end up with an early trans rebuild as suggested.
Get onto the Dgas mob,extra power/economy to help out with the job.(see my post in the tech forum)
Andrew

Redback
17th March 2008, 08:48 PM
Until it breaks...

We had to replace a Defender gearbox when 5th gear pretty much exploded. Towing a tandem box trailer with canvas covered frame. 120 000km on the clock.

I have 166,000ks on the clock, my Disco has towed for it's whole life, a caravan (don't know weight 18ft van) before we bought it and a camper trailer now (1.3 to 1.5ton)

If you drive the car correctly and don't labour the car in 5th it should last.

Baz.

harryw
17th March 2008, 09:30 PM
Hi Andy

I assume by 4th gear you mean Drive as i have an auto.

best regards