Using 5th while towing?

Submitted: Thursday, Oct 30, 2003 at 15:13

ThreadID: 8201 Views:2456 Replies:12 FollowUps:17

This Thread has been Archived

RussellV

Hi All

Just wondering how many people use 5th gear when towing. I have a GU Patrol 4.2TD and I've heard that prolonged use of 5th gear when towing (say a 2t trailer) can cause long term damage to the gear box. Is this a bit of a myth or is this legit? What are your methods/gear selection when you're towing on extended trips?

Thanks in anticipation!

Back Expand Un-Read 0 Moderator Share

Reply By: Duke-Attie - Thursday, Oct 30, 2003 at 15:22

Thursday, Oct 30, 2003 at 15:22

80-90kmh in 4th......... 5th gear is a very damagable thing when abused..... Some cars worse than others............

AnswerID: 35715

Reply By: petprass - Thursday, Oct 30, 2003 at 15:35

Thursday, Oct 30, 2003 at 15:35

I rarely tow in 5th gear. Sometimes when the road is flat and no wind, but really there is no advantage in fuel saving by doing that as my Patrol just guzzles the petrol when towing - so a saving of a couple of mls of fuel is hardly noticeable.

Having said that my 5th gear went on my 2000 GU at around 85K - even though I hardly used it when towing. The 5th gear problem is due to a short machined 5th gear spline and eventually will go as the gear wears whether you tow or not. That is for 2000 build vehicles. What year is your Patrol?

Peter

AnswerID: 35718

Follow Up By: RussellV - Thursday, Oct 30, 2003 at 15:37

Thursday, Oct 30, 2003 at 15:37

My Patrol is 11/99 model. All is well with 5th at the moment - however I am coming up to the 85k mark!

FollowupID: 25796

Follow Up By: petprass - Thursday, Oct 30, 2003 at 15:44

Thursday, Oct 30, 2003 at 15:44

As 11/99 is borderline, I would check with Nissan to see if your truck has the short machined spline or not. Might be easier to get it repaired under warranty if anything happens at a later date by "registering" your concern. Hope though that you will not have to worry about it at all.

FollowupID: 25797

Reply By: Member - Melissa - Thursday, Oct 30, 2003 at 16:15

Thursday, Oct 30, 2003 at 16:15

We've got a 4.5L ST GU Patrol and quite often use 5th when towing our campertrailer out on the open highway. We reckon fully loaded the trailer's about 1.2t and once we get up to speed on a good road, the GU hardly seems to know the trailers there. Of course, this only applies to nice flat stretches. Throw a few hills in and we have to drop back to 4th.

:o) MelissaPetrol 4.5L GU Patrol &
Camprite TL8 offroad camper

AnswerID: 35719

Reply By: howesy - Thursday, Oct 30, 2003 at 18:34

Thursday, Oct 30, 2003 at 18:34

I tow heavy loads every time I go away which is about 4 to 6 times a year. I use fifth regularly but only in little or no load situations. In other words the car is cruisin with my foot barely touching the gas. If your not sure if your got load or not (some people can detect engine & driveline load easier than others) then a good investment would be a boost guage. They are an easy install.

AnswerID: 35730

Reply By: Trekker - Thursday, Oct 30, 2003 at 19:49

Thursday, Oct 30, 2003 at 19:49

Hi Russel & All ,

I have a Toyota Surf 2.4 litre Diesel with manual box, towing a 16 ft Jayco Freedom poptop, and I use 5th gear as much as possible, changing down when ever the road conditions warrant it. I travel at 80 to 90 kmh which keeps my revs between 2200 & 2500.

I have a friend who has an Explorer with an auto box and he locks it in 4th as the box is continually changing up & down when he selects full auto.

Gordon

AnswerID: 35740

Reply By: joshinthecity - Thursday, Oct 30, 2003 at 20:47

Thursday, Oct 30, 2003 at 20:47

I believe it was ALL series 1 and 2 Patrols that had the short spline 5th.

josh.

AnswerID: 35745

Follow Up By: GUPatrol - Friday, Oct 31, 2003 at 10:07

Friday, Oct 31, 2003 at 10:07

Josh,
The spline problem was introduced in the machining tolerances when Nissan reviewed the g/box as it introduced the 3.0L model.
The series 1 patrol uses the same g/box as the GQ with a few revisions only and it is OK.
One way to identify it is by looking at the box/bellhousing (they are different) but you need to know what you are looking at or have two side by side.
Will

FollowupID: 25837

Follow Up By: Member - Melissa - Friday, Oct 31, 2003 at 12:46

Friday, Oct 31, 2003 at 12:46

Will,

Are we talking 2000 or later models then???

:o) MelissaPetrol 4.5L GU Patrol &
Camprite TL8 offroad camper

FollowupID: 25854

Follow Up By: GUPatrol - Friday, Oct 31, 2003 at 13:04

Friday, Oct 31, 2003 at 13:04

Melissa,
Yes problem was introduced in 2000 (by a manufacturing tolerance fault) when the 3.0L model was introduced and fixed when they realised it which was in 2002.
So if you have a GU series 1 you are safe, if you have a series 3 you are also safe but any series 2 is a question mark.
Will

FollowupID: 25856

Follow Up By: Geoff - Saturday, Nov 01, 2003 at 07:48

Saturday, Nov 01, 2003 at 07:48

Will,

You are correct in saying that it's a tolerance issue, but it's not restricted to '00-'02 models.
The problem first appeared with the intro of the 4.2td in mid '99.(Source: Nissan and the fact I know of a couple)

I'm hoping mine (11/99 4.2td, 70k) goes soon to avoid any arguments re warranty (extended), however I have been told by Nissan Customer Service that they are repairing 'boxes well out of warranty.

Cheers
Geoff

FollowupID: 25904

Follow Up By: GUPatrol - Monday, Nov 03, 2003 at 10:06

Monday, Nov 03, 2003 at 10:06

Geoff,
G'boxes were not revised when the turbo 4.2 was introduced... they were revised for the introduction of the series 2 3.0L six months later, the 4.2 turbo was introduced in april 99, therefore models affected are about 10/99 to 2002 when the series 3 released.
Will

FollowupID: 25996

Follow Up By: Geoff - Monday, Nov 03, 2003 at 19:49

Monday, Nov 03, 2003 at 19:49

Sorry Will,
Series 1 are affected. Just ask those who've had theirs repaired.
As I said, I personally know of 2 series 1 4.2td's that have done 5th gear, both built mid '99.
Nissan acknowledge that it's a problem for ALL GU 4.2td's built prior to the rectification.
Even going by your dates there is a 6 month window of Series 1 production where the 'box would be suspect (10/99 to 3/01), and it is therefore incorrect to say that only Series 2 are at risk.
Cheers
Geoff

FollowupID: 26032

Follow Up By: GUPatrol - Tuesday, Nov 04, 2003 at 10:55

Tuesday, Nov 04, 2003 at 10:55

I have just called Nissan to confirm, vehicles affected are series 2, productions years 2000 to 2001.
They said some faulty units may have been fitted to 11/99 models but unlikely and some may have slipped past 2001 but unlikely.
The number of gearboxes affected is not many, within those dates there are vehicles which are fine.

Will

FollowupID: 26067

Follow Up By: Geoff - Tuesday, Nov 04, 2003 at 12:15

Tuesday, Nov 04, 2003 at 12:15

How do the pre-Series 2 'boxes that HAVE blown fit into this??

Geoff

FollowupID: 26075

Follow Up By: GUPatrol - Tuesday, Nov 04, 2003 at 14:26

Tuesday, Nov 04, 2003 at 14:26

OK Geoff, this is the way it goes as explained to me by Nissan.
1-Nissan reviews g'boxes as it plans to introduce the 3.0L engine
2-All variants use same g'box from here on so g'box goes to production just before the introduction of series2 (hence very late series 1 11/99) modesl may have the problem but at that stage and since then the pile of old/new g'boxes is mixed at the plant.
3-3.0L engine is released (series 2), problem first appears in 3.0L models because of lower ratios diff and high engine output per stroke (4cyl) compared to 6cyl.
4- Nissan discovers stuff up in tolerances at manufacturers end and problem rectified.
5- Since there was a mixture of gearboxes old/new not all vehicles are affected.
6- Series 3 g'box is reviewed again for the introduction of the 4.8petrol model

FollowupID: 26084

Reply By: SupaMav - Thursday, Oct 30, 2003 at 21:46

Thursday, Oct 30, 2003 at 21:46

I had to get a replacement 5th gear as well as a bearing kit in my SD33T-powered MK because the guy I bought it from used it to tow horse-floats. The rest of the 'box was fine, but 5th was, how you say, Wallaby Bob's brother. $2700 later and all is good ;-). This is not a new problem.

AnswerID: 35754

Reply By: Member - jaksun - Friday, Oct 31, 2003 at 09:27

Friday, Oct 31, 2003 at 09:27

Do Land Cruisers suffer the same problem as Patrols in using 5th gear for towing caravans or heavy trailers.

AnswerID: 35777

Follow Up By: GUPatrol - Friday, Oct 31, 2003 at 10:11

Friday, Oct 31, 2003 at 10:11

All gearboxes do....
5th is overdrive and it is a very fine small gear (unlike the other gears).
The best gear to tow with is 4th as it is direct, you can change to 5th while cruising down hill with little throttle and only over 80kms/hour.
Never load/lugg in fifth even when not towing!! ie: speed dropped below 80 you need to accelerate (even slight) change back...
Will

FollowupID: 25839

Follow Up By: Big Trev - Friday, Oct 31, 2003 at 10:48

Friday, Oct 31, 2003 at 10:48

Have to agree with that IF THE VEHICLE IS LABOURING OR FALLS BELOW THE IDEAL REV/TORQUE RANGE, then you should be in 4th gear. If the vehicle is performing fine in 5th, meaning you have acceleration then it is OK.

I am a huge fan of having the right specced vehicle doing the job. Cubic capicity is the only way to go. Using 4 cylinder vehicles or 3 litre 6 cylinder vehciles for heavy prolonged towing is asking for trouble for the whole driveline, tubo'ed or not. You are asking the vehicle to do more than it was designed to do.

I have been a truck driver and truck driver trainer for over 25 years. This sort of discussion is not different for trucks. Mind you the design of the transmission is significantly different, but the engine/driveline spec stuff is just the same, just remember most 4X4's ARE light trucks.

FollowupID: 25841

Follow Up By: GUPatrol - Friday, Oct 31, 2003 at 11:03

Friday, Oct 31, 2003 at 11:03

Trev,
You say:
"If the vehicle is performing fine in 5th, meaning you have acceleration then it is OK"
That is where the problem is, the 3.0L for example will pull away in fifth from 60kms/h, the transmition is fairly low and with lots of torque on tap people just go for it.
A friend of mine ad the 5th gear problem with his 2000 GU 4.2 when it broke he was going up hill at 50kms in 5th, he said "I always do it"...
The Patrol g'box is built like a truck and it is stronger than many light trucks and buses I have seen, same for the diffs and axles, the 5th gear problem does not show even if abused unless you have a 2000 to 2002 model (basically all series 2) which had a tolerance defect at manufacturing, including petrols, however petrols don't show it so much because the torque range is at much higher RPM and the ratios are higher.
Will

FollowupID: 25843

Follow Up By: Big Trev - Friday, Oct 31, 2003 at 11:15

Friday, Oct 31, 2003 at 11:15

I should have added that 80k limit mentioned by some, is a very good recommendation. I have an '89 TD42 Ford Patrol / Nissan Maverick and NEVER drive in 5th below 80k's, mind you if you check you ideal rev/torques range for the engine, then it probably relates to the same.

You say:
That is where the problem is, the 3.0L for example will pull away in fifth from 60kms/h, the transmition is fairly low and with lots of torque on tap people just go for it.
A friend of mine ad the 5th gear problem with his 2000 GU 4.2 when it broke he was going up hill at 50kms in 5th, he said "I always do it"...

I don't think a 3 litre 4X4 with a tralier of 1.5 to 2 tonnes would "pull away" in 5th from 60k. I could almost guarentee that that vehicle would be busting its balls to do that, shuddering, etc.

Your friend needs to re-read the operators manual in the glove box if he drives uphills at 50k's in 5th "all the time", I am sure that there would be some writing about such things in the manual. Maybe you should recomend some good/appropriate driver training organisation to him.

FollowupID: 25844

Follow Up By: carazy merredin wa - Friday, Oct 31, 2003 at 21:31

Friday, Oct 31, 2003 at 21:31

80 series box is a big mother & heavy, 5 th gear is right in the middle of the gear box so that the load on the bearings is even. Plus gear/transfer boxes are oil pressure fed-they have oil pumps in em! These boxes never require attention.
The 75 series & pre models boxes are just crap, only use 5th for going down hill & change oil every 20k!

FollowupID: 25885

Reply By: Willem - Friday, Oct 31, 2003 at 10:10

Friday, Oct 31, 2003 at 10:10

This subject comes up regularly every 3 months or so.Have a look through the forum archives.

It is advisable not to let the gearbox of your vehicle labour in 5th gear as 5th is an overdrive gear. Your 4x4 might not sound like it is labouring under the strain and some vehicles may drive further whilst towing in 5th but ultimately there is damage occurring all the time and and sooner or later it will fail...just when you least expect it to.

Why try to damage your vehicle by overstressing its components? There is no logic to it.

Willem

Always going somewhere

AnswerID: 35782

Reply By: David N. - Friday, Oct 31, 2003 at 16:23

Friday, Oct 31, 2003 at 16:23

Partly urban myth, part true.
I have a 13 yr old GQ TD42 (turbo) and have been using 5th for towing at appropriate speeds since day 1. (I don't however let it labour in 5th). I tow various trailers right up to the legal limit. Gearbox is as good as new.

It's a darn shame that Nissan got it wrong for a while with some GU's (problem now fixed) as the GQ 4.2litre gearbox has a perfect clean bill of health and the gearbox is by far the most rugged in the industry. The history on the GU gearbox 5th gear splines failing is well documented- do a search and you should be able to find pretty close to exact dates affected.
As long as yours is not built in the affected dates go for it! Why rev the guts out on your engine rather than use the gearbox as intended. (I'm talking highway speeds- 80kph and more, as it would not make sense to use it towing at lower speeds as you'd be right out of your good torque band.)
My cousin has just taken delivery of his 5th 4.2 diesel Patrol - he trades them in approaching 400,000 kays and has never had ANY mechanical problem. The earlier non-turbo ones were after-market turboed from near new. He even had a GU with supposedly suspect 5th gear but got rid of it with 375,000 on the clock and no problems with the gearbox or anything else! BTW, he drives them hard!

AnswerID: 35817

Reply By: Peter Guy - Friday, Oct 31, 2003 at 19:00

Friday, Oct 31, 2003 at 19:00

I have been towing camper trailers for many years behind a 94 v 6 Jackeroo and now a GU 98 2.8 diesel Patrol. Both vehicles completed over 170,000 ks and have always used 5th gear, but only when travelling over 80 kls per hour on flat or down hill roads. Any strain and decrease in revs then its down to 4th gear.
The 2.8 patrol pulls and accelerates surprisingly well in 5th but keep an eye on the tacho and keep the revs up over 2000 rph.
You should have no probs.

AnswerID: 35831

Follow Up By: Gronk - Friday, Oct 31, 2003 at 21:56

Friday, Oct 31, 2003 at 21:56

I tow a camper trailer behind a 3ltr td jackaroo and use 5th gear from as low as 1500rpm(with sensible use of the throttle),but most of the time like to keep the revs around 2800rpm because thats where the most acceleration occurs due to the torqe and power curves meeting.Have never had problems with any of my engines (10cars-1millionkms) because I believe in never UNDER reving an engine,keep it spinning freely in the middle of its rev range(ie no stress).Sure to have a couple people disagree with me ?

FollowupID: 25890

Reply By: Member - Eskimo - Sunday, Nov 02, 2003 at 18:43

Sunday, Nov 02, 2003 at 18:43

I always thought laboring damaged the engine?
How does an engine laboring affect the gear box???

Wow! am I cute
If yer ain't fishing, Yer ain't livin
Richard

AnswerID: 35977