Gu problems

[Lewie119]

Hey guys, so I’ve got a factory blacktop TD42T I never really drove it on the highway much so I never realised but I can barely pull 110km/h without maxing out on revs wondering if this is normal or if something’s wrong with it and if there are any ideas of what could be causing this?

[mihit]

Auto? Manual? Clutch slip? TC? What do you consider "max revs"? What size tyres? What ratio diffs? What were the results of the compression test?

[Stropp]

Hey guys, so I’ve got a factory blacktop TD42T I never really drove it on the highway much so I never realised but I can barely pull 110km/h without maxing out on revs wondering if this is normal or if something’s wrong with it and if there are any ideas of what could be causing this?

As Mihit says lots of things can effect it but I’d be tyresize or diff ratios

[Lewie119]

Auto? Manual? Clutch slip? TC? What do you consider "max revs"? What size tyres? What ratio diffs? What were the results of the compression test?

2001 5 sp manual 33’s as far as I know stock gearing. Haven’t had a compression test done, just looking for any ideas. Currently at about 100km/h I’m sitting at 3k revs and struggles to get to 110

[mudski]

2001 5 sp manual 33’s as far as I know stock gearing. Haven’t had a compression test done, just looking for any ideas. Currently at about 100km/h I’m sitting at 3k revs and struggles to get to 110

A lot of things could be in play here but these TD's in stock form are slugs. To put it plainly. But they do respond well to a little tickle. Better turbo, bigger intercooler and a nice new 11,or 12mm injector pump and they'll pull Jesus from his cross.
My TD has had a good tickle, and towing my van I can overtake with ease in 5th, and on a hill, and hold it pegged at 130 if I wanted too.

But depending on how may k's your TD has done, it could just be time for new injectors maybe. Dunno.

3k rpm at 100kph is a lot. Thats way out of its rev/ power range in my opinion. With 4.11 diff ration. Mine will sit on 2450rpm at 100kph and I still think its a tad too high.

I reckon you might have 4.3 diff ratio in yours, or the tacho, or speedo is reading wrong. From memory, Early factory GU TD ran either 3.9's or 4.11's. You can test this out. Raise the back end up and count how many times the wheels turn to one turn of the diff.

[Lewie119]

Thanks mate I’ll give it a good look

[mihit]

I -assume- the GU carried forward the 4.11 ratio diffs. Unless your wagon has been converted from auto?

Since they develop max torque at just off idle (~280 torques at 2k rpms) that does seem excessive...

But since mine all have random tach/speedos that "work" intermittently... I just drive by ear and don't exceed the posted speed limit. Couldn't tell you what rev/speed.

It would seem that power is being lost, or not enough made... The suggestion of injectors is good. There's also a filter screen in the top of the Injector pump inlet, you need small sprung inside-calipers to pull the thing out. Also obviously bleed the fuel filter and injector line at the same time.

No brakes calipers sticking? Park brake? Trans and diff oils fresh and right viscosity?

33" tyres are bigger than stock (31"?) so you may want to double check your speed actual (GPS, phone app, whatever) against the indicated...

[Wizard52]

2001 5 sp manual 33’s as far as I know stock gearing. Haven’t had a compression test done, just looking for any ideas. Currently at about 100km/h I’m sitting at 3k revs and struggles to get to 110

Mu UTE 4.2TDi does 2300rpm at 100kph with standard 265/75 tyres so either it is not factory standard or speedo is way out. At 3000rpm it would be a bit noisy.

[Brokenpatrol]

Hi there I have a 2004 gu and I’ve got a problem with my auto, I have heaps of power in 1st and 2nd but then loose boost and throttle response when I goes to shift into 3rd. I have replaced the original motor with and other low km zd30di have u any ideas??

[mihit]

have u any ideas??

Ideas? Start your own thread? Rather than hijack one about TD42s...

Difficult (for me) to rule out issues, or troubleshoot, on automatics so i just blame "computers"
You may have needed swap/reprogram "computers" when you swapped out engines. Or you have failed to connect a sensor, etc.
Hopefully someone who can help will find your post...