Gq/Gu 5 speed manual strength?

[Bartso]

Hi guys I'm talking about the td/tb 42/48 5 speeds how much hp can one of these handle are there any upgrades?
What's the mist power you've seen one have

Cheers

[toughnut]

Just remember to check if it has the larger 5th gear in it. Especially if you are doing extended driving in low range at any sort of speed like a nave stage etc. If you don't use 5th that much then don't stress too much about it. This was mostly in the early series 1 GUs.

[MikeH]

It depends how you drive it. if you are sensible they can handle a built LS-2 forever and a monster turbo TB48 for short durations with a gentle driver. They are very reliable. However breaking them is not unheard of. I know of one that did second gear, but they had a 900Nm motor in front of it.
5th gear dies commonly from people towing in 5th and running the revs too low because they think it makes better fuel economy (it usually doesnt). It strips the spline out of the centre of the gear and you can still drive the car if you dont put it into 5th.

If you do manage to break a few gearboxes then Albins makes a replacement gearset hich they stuff into the nissan housing. Its nearly 10 grand though. If you find yourself needing one then 10 grand wont be a lot compared to what you have spent on your motor.

If you are putting some decent horsepower in front of one I recommend putting Redline MT90 into it and the transfer case. It'll cost you about $300 for the oil but it makes them run a lot cooler.

Often they are a bit crunchy into lower gears, most of the time this is caused by people using the wrong spec (not weight, spec) of oil in them. they have to have a GL4 oil. A GL5 will damage the synchros. Lots of people who should know better mke this mistake.

they make a hell of a racket when idling in neutral, especially with lumpy cams and light flywheels. they all do it, dont worry about it.

[Burdy]

It depends how you drive it. if you are sensible they can handle a built LS-2 forever and a monster turbo TB48 for short durations with a gentle driver. They are very reliable. However breaking them is not unheard of. I know of one that did second gear, but they had a 900Nm motor in front of it.
5th gear dies commonly from people towing in 5th and running the revs too low because they think it makes better fuel economy (it usually doesnt). It strips the spline out of the centre of the gear and you can still drive the car if you dont put it into 5th.

If you do manage to break a few gearboxes then Albins makes a replacement gearset hich they stuff into the nissan housing. Its nearly 10 grand though. If you find yourself needing one then 10 grand wont be a lot compared to what you have spent on your motor.

If you are putting some decent horsepower in front of one I recommend putting Redline MT90 into it and the transfer case. It'll cost you about $300 for the oil but it makes them run a lot cooler.

Often they are a bit crunchy into lower gears, most of the time this is caused by people using the wrong spec (not weight, spec) of oil in them. they have to have a GL4 oil. A GL5 will damage the synchros. Lots of people who should know better mke this mistake.

they make a hell of a racket when idling in neutral, especially with lumpy cams and light flywheels. they all do it, dont worry about it.

yea i no alot of blokes that have run a 80w90 GL5 or 75w90 GL5 grade oil in there gearboxes for years,most oils these days that are a GL5 spec oil across most brands,there arent too many that have a GL4 spec

[MikeH]

Do some research, it stuffs the brass synchros. Believe me I've done it myself.

[Maverick93]

Sounds like some good info guys, last month I did all the oils in my GQ... I used a workshop manual and the penrite site, both said recommended


http://www.penriteoil.com.au/pis_pdfs/H ... 202010.pdf

... it doesnt say anthing about GL4... sounds like I'll need to drop the oil and change it, any recomendations?

Maybe? http://www.penriteoil.com.au/products/g ... nual_trans
or http://www.penriteoil.com.au/products/g ... ear_oil_80" onclick="window.open(this.href);return false;

Thanks

[Burdy]

I have been doing some research on it with different oils and found there are still a fair few different brand of oils with the GL-4 spec oil i was suprised, i found this oil the weight of the oil is a bit different (DURAGEAR SAE 75W-85) it also comes in an 75w-90 weight oil aswell but i got the 75w-85 with a GL-4 spec hopefully it does the job

[Burdy]

Sounds like some good info guys, last month I did all the oils in my GQ... I used a workshop manual and the penrite site, both said recommended


http://www.penriteoil.com.au/pis_pdfs/H ... 202010.pdf

... it doesnt say anthing about GL4... sounds like I'll need to drop the oil and change it, any recomendations?

Maybe? http://www.penriteoil.com.au/products/g ... nual_trans
or http://www.penriteoil.com.au/products/g ... ear_oil_80" onclick="window.open(this.href);return false;

Thanks

the top link ya got there mate on the bottom right hand corner it's states that its a Api GL-5 spec oil but the second and third link are the right spec oil

[Bartso]

Looking at this page they seem to think you can go 800hp+ if you change the input shaft and run a cooler
http://www.bspturbo.com/nisan.htm" onclick="window.open(this.href);return false;

[Clanky]

This has me intrigued that an oil can damage a gearbox. I trust this is relevant to the thread about longevity in the Patrol box
Are there any manual gearboxes that dont use brass type synchro rings?

http://www.thesamba.com/vw/forum/viewtopic.php?t=276529" onclick="window.open(this.href);return false;

http://www.benzworld.org/forums/unimog/ ... -plot.html" onclick="window.open(this.href);return false;

So confusing is the interwebnets information.

Of note is the technical data sheet at Redline oils which has some information mostly related to "frictional" properties of certain oils to enhance synchromesh operation. So maybe the GL5 extreme pressure friction modifiers dont damage synchros, but allow them to 'slip' hence not allowing them to work as designed. Thus the damage may come from being heavy handed with the GL5.
(note 2nd last column) http://www.redlineoil.com.au/Uploads/Do ... 002_03.pdf" onclick="window.open(this.href);return false;