noise in GQ shortie...help needed

[jigga]

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i seem to get a noise at highway speed, but not all the time in my gq shortie. it fairly standard, i just have a 2inch lift, thats it. is seems happen though when im on a 100 or so and back off the accelerator. it only happens when i back off. i can feel it though my feet/firwall..

what could this be?

[Doggy]

uni joints in the rear drive shaft probably. To check them, put the transfer case in neutal, gearbox in neutral..climb underneath and see if there is any play in the tail shaft. Just make sure you have the handbrake on or blocks or something so you dont get run over. Have you got gear box spacers to lessen the angle of the tail shaft to account for the lift?? If you dont, that could also be a problemo
Its a shorty, its supposed to make noises

[JeSTeROCK]

Most likely your rear tail shaft

Check your unis (flat spots) and slip (play) and angles of the of the unis.

Diff and gear box uni angles should the same. When you raise a shorty the pinion angles up towards the gear box, it needs to parallel with the gearbox

Grease all nipples before you go into it too far.

[jigga]

so i need to do this even tho it was only a 2inch lift? i will check the rear tailshaft and grease unis also.ta

[Nelso]

A 2" lift is definitely enough in a shorty to cause a vibration in your rear tailshaft. They all do it as the tailshaft is so short.

The easiest cure is to drop your gearbox crossmember 12mm. You can buy packers to do this or if your handy they are easy to make.

[jigga]

definately not handy. what do you think it would cost me to get someone else to do it? eg. is it a big job?

[Madmac]

definately not handy. what do you think it would cost me to get someone else to do it? eg. is it a big job?

no its not a big job. all you have to do is buy the spacers, place a jack under the cross member, remove the 8 bolts, lower the jack an inch or so, slip in the spacers, then stick the 8 bolts back in

[mudmav]

GEARBOX PACKERS ARE THE DEVIL!!!!!!!!!!

Put some longer lower control arms in instead

[Nelso]

Yeah I do agree its a better option, especially if you still have standard lower control arms. They are as week as p1ss and will probably break the first time you push your car 4wding.

Just be prepared to pay a bit more for your adjustable lower control arms compared to the cheap option of crossmember packers.

[henry]

My shorty makes noises too.What do longer lower control arms do? how do they fix the vibration? dont longer lower arms point the pinion down causing worse angles?

[rod baker]

cheap and easy rear double cardan rear shaft for a shorty
buy a second hand front tail shaft from a long wheel base and shorten it to fit the rear works well
did mine cos it was raise to inches and the transfer was moved backwards 4 inches so i fit a 3.8 v6 and auto runs a treat

[Nelso]

My shorty makes noises too.What do longer lower control arms do? how do they fix the vibration? dont longer lower arms point the pinion down causing worse angles?

They rotate the diff to re-align the universal joints so they are the same angle. If they are at different angles the driveshaft is dynamically out of balance, therefore will vibrate.

Once you go more than a couple of inches lift the angles start to increase putting too much strain on the universal joints. That's when you need to go to a double carden joint on the front uni and rotate the diff so the rear uni runs in a straight line.

If you intend on not lifting your shorty more than a few inches don't bother with a double carden set up as they can cost a bit to do them properly. Toyota double cardens and driveshafts are a lot smaller than Nissan ones and will be your weakest link in your drivetrain. You can fit a DC joint out of a Cadillac (about $800-900 fitted and balanced) but it will be hard to source parts if it breaks touring outback and once it wears out is a throw away job. Mine runs the same Nissan uni's and is rebuild-able when it wears out, and is near indestructible, but it will set you back $1500 to get fitted and balanced. Way too much to spend unless you need to.

[Nelso]

cheap and easy rear double cardan rear shaft for a shorty
buy a second hand front tail shaft from a long wheel base and shorten it to fit the rear works well
did mine cos it was raise to inches and the transfer was moved backwards 4 inches so i fit a 3.8 v6 and auto runs a treat

I'm curious to know why they run a double carden in the front of a long wheelbase but not a shorty when they share the same engine and drivetrain? I don't know about longies as every gq I've worked on has been a shorty, but I know shoties only run universal joints at both ends of the front driveshaft.

Can anyone confirm rod's statement.

[viperguy]

if the noise is like a vibe noise it will be uni's.. if its like a grinding type of sound it will be spline. its caused by the shaft being extended more after u have lifted your truck and having less contact area between splines of inner and outer tube. a good fat grease will benifit greatly if used regularly. pump it into the spline nipple.

as for d/c r standard shafts.. i have 5 inch coils in my shorty and still run standard shaft. it is flipped though. better to set up ur lower arms to give matching transfer-pinnion angles and keep standard shaft. ive had my lift for about 3 yrs now and have no drama with shaft.

[henry]

I think what rod baker was eluding to is hilux's run a double cardin front shaft not patrols.

Viperguy, what do you mean by "flipped" what have you flipped to reduce the vibration?

Its good to hear that you can keep the standard shaft with some driveshaft angle tuning.

[viperguy]

flipped as in swapped end for end.. and quit frankly i dunno why i did this but it seems to have done something for the positive.. i think lwb guys flip them to get the fat part away from the cross member or something..

[dwaynes]

definately not handy. what do you think it would cost me to get someone else to do it? eg. is it a big job?

no its not a big job. all you have to do is buy the spacers, place a jack under the cross member, remove the 8 bolts, lower the jack an inch or so, slip in the spacers, then stick the 8 bolts back in

Madmac where did you get the spacers from?

[rvh96]

MQs use a double cardan in the front shaft not GQs and unless your GQ is a 2.8litre it wont fit the rear anyway. the front d/cs of nissans and toyotas are the same unit the only differrance is flange patten these d/cs are not designed to drive the whole truck and will not last long if you make them. We use sagnaw d/cs as used on caddies,buicks etc which i can supply them brand new in new shaft for $ 775 ready to bolt on or fit a new one to your shaft for $475 they are rebuildable and parts are availiable .We also do a shaft with a cv joint one end and double cardan other end for exteme angles for buggies and such $POA Up to 2 inch in shorty you should be able to get away with spacers under the transfer case

[Stu'sBeast]

cheap and easy rear double cardan rear shaft for a shorty
buy a second hand front tail shaft from a long wheel base and shorten it to fit the rear works well
did mine cos it was raise to inches and the transfer was moved backwards 4 inches so i fit a 3.8 v6 and auto runs a treat

Pretty sure only the ute's have the double cardin front

[rod baker]

every shorty i have had ,about 5 now have had a double cardin in the front but they were all MQ/MK i do not know what a hilux runs and i dont alude to anything this is what i did

ripped out the complete drive line. I used a tl100 transfer(100$) from a long wheel base, mounted approx 100mm further back fitted a 2 inch spring lift angles were shit and different so used the original font tail shaft which was a double cardan and shortened it in my mates lathe, pressed it all back together and hey presto for the front i needed a longer one than original .
To have it made was bloody expensive so went to wrecker and bought a front double cardan from a long wheel base for $100 and again shortened it in my mates lathe this was all done so i could run a commodore v6 and auto it makes for a cheap conversion it goes very well 0 to 100 with 3 adaults 13 sec it cost me about 600 plus engineers 380 and as a daily driver its great and it tows well unfortunatly the wife likes it to
rod

[henry]

cheap and easy rear double cardan rear shaft for a shorty
buy a second hand front tail shaft from a long wheel base and shorten it to fit the rear works well
did mine cos it was raise to inches and the transfer was moved backwards 4 inches so i fit a 3.8 v6 and auto runs a treat

when i said eluding to i was trying to understand your description in the above thread not that i meant you were making some thing up.

[Josh_GQ]

I used standard shaft in my shorty with a 5 inch lift. Just got adjustable upper arms ( just over $300 for pair) It still had a very slight vibration if the grease wasn't kept up to it.

It is beter to shorten your upper arms than lengthen the lowers as it will keep your tyre central in the arch at full compresion

[jigga]

i will try to grease all the joints...so it is the tail shaft, even though it only happens when going above 80km and only when taking my foot of accelerator.

[henry]

Mine does exactly the same thing, only above 80 and when im coasting on the accelerator, under power its ok and under full deceleration its ok. let us know how you go with it dude.

[Jimmu]

Mine has the grinding noise when backing off above 60klms, most noticeable coasting at 110. I suspect as viperguy said it is the spline. There appears to be a bit of play in it. I have fitted a 25mm tailshaft spacer hoping that would bring the spline back into spec but it made no difference.

It is really starting to piss me off to be honest and if I cannot work it out I think I will drop the back end down an inch or so.

If it is the spline, which it sounds like it is from Viperguys description it will changing the angle of the diff to correct the 'Dynamic balance' make a difference?

Maybe those diff wedge things could assist?

Any help will be appreciated.

Jimmy

[Jimmu]

Anyone here know there stuff about drive shafts and fixes?

Jimmy

[Nelso]

Mine has the grinding noise when backing off above 60klms, most noticeable coasting at 110. I suspect as viperguy said it is the spline. There appears to be a bit of play in it. I have fitted a 25mm tailshaft spacer hoping that would bring the spline back into spec but it made no difference.

It is really starting to piss me off to be honest and if I cannot work it out I think I will drop the back end down an inch or so.

If it is the spline, which it sounds like it is from Viperguys description it will changing the angle of the diff to correct the 'Dynamic balance' make a difference?

Maybe those diff wedge things could assist?

Any help will be appreciated.

Jimmy

Uni's being out of alignment will cause this grinding noise. The diff wedges are for realigning your pinion angle to match the angle of the shaft at the back of your transfer case. Both universal joints need to be at the same angle to be dynamically balanced, then your noise will most likely disappear.