[31zook]

hey guy's i went for rego yesterday, failed on a little bit of rust in the floor pan that i have never seen before, oh well im getting good at cutting out rust. And my clutch cable got caught in the steering rag joint and ripped it all apart, spewin.

How hard is it to rebuild a sierra 5 speed gear box? mine has a high pitch whine and a sloppy feel, is this a take to a shop thing, or a careful home job?

Also would filling it with diff oil make it whine? i never checked what oil it needed so now it's full of diff oil, i keep meaning to change it but forgeting and i can only test it when im driving to the rego mans shop.

Also does a sierra 1.3 head have a gaskit between the dizzy and the head? mine is loosing oil there, but im not sure i put on the right gaskit, because it broke... do i need one there?

cheers

[Rusho]

You need a gasket between the head and the dizzy housing. Can't help
with the gearbox thing, sorry

[31zook]

Cheers rush, ill try to find one now

[Rusho]

Or make one.

[want33s]

It is just an O ring between dizzy and head isn't it?
Fit a new one with a smear of grey gasket silcon on it... no more leak!

VMX80* is recommended for gearbox.. Is a bit thinner than EPX 80W90 used for diffs..

*Seems Castrol have dropped VMX80 and now make VMX-M75W/85 as its replacement.

Rebuilding a Sierra box isn't hard but you will need a press to get bearings on and off.

[31zook]

yep repco in greenhills has vmx80 bought 2L of it.

ok i have a press, i might have to buy some pressing die's, but thats it's not way hard is good

[clem430]

yeah i put new bearings in my gearbox, didn't stop it whining though. but i used a bearing puller and then heated the new bearings up in the oven and they just slid on nicely

[ninjadaniel]

i was told that if the whining is only in certain gears then its the gearbox, if it whines at high speed then its transfer case- so far this theory has been true for my experiences.

[foolsp33d]

VMX80 FTW! AWESOME stuff for both gearbox and transfer! (drain old oil from both box's and refill both from in the car.. remove shifters and undo the fillbolt, fill till it starts to trickle out the fill hole. reassemble!) better way than layin on the ground squeezin like a mofo.

[BlueSuzy]

foolsp33d wrote:

VMX80 FTW! AWESOME stuff for both gearbox and transfer! (drain old oil from both box's and refill both from in the car.. remove shifters and undo the fillbolt, fill till it starts to trickle out the fill hole. reassemble!) better way than layin on the ground squeezin a mofo.

Id rather squeeze a mofo.

[31zook]

Oh, haha I used diff oil SAE90-80W in my transfercase, I'll buy some more vmx and change the oil in there as well. Ok so I'll order my gearbox rebuild kit soonish and try a different oil in the mean time.

[303zuke]

Diff oil is perfectly OK for the gearbox, it's what is specified in the manual, it's just that VMX80 works BETTER. The only diff oil you can't use is LSD oil as it will attack bronze bushes and synchros in the gearbox.

You can also use ATF fluid which will greatly improve synchro operation and cold morning gear changes, but it's not recommended as a heavy duty oil for uses like towing.

[losfer]

ninjadaniel wrote:

i was told that if the whining is only in certain gears then its the gearbox, if it whines at high speed then its transfer case- so far this theory has been true for my experiences.

if the noise goes away or is quiter in 4th gear , its generally a gearbox issue , as 4th gear is direct drive from input to output shaft , and the bearings are not as loaded up as they usually are as when they are loaded up by the lay shaft. This theory doesnt always prove true with severely worn mainshaft bearings.

most of the time if the issue is in the transfer , it will be the lay shaft has severe pitting/wear on it where the needle rollers run on the shaft , when the noise is most apparent , you can actually feel it rumbling through the transfer lever.

Although 99% of the time i can locate the source of the noise on a test drive , i always run it up in 4th gear on the hoist to verify , as i have been caught out once or twice before.

[v.w.dave]

What about crunching going into 2nd gear with no other problems. I have no bearing noises no sloppy stick just a crunch into 2nd gear. I know its going to be the syncro and or 2nd gear it self but how hard is it to replace? or get it apart? ( I have built close to a 100 or more volkswagen and a few fors ranger boxes and i have a press and plenty of tools) just want to know how hard it is to build?

[31zook]

im guess the trade from VW to zook willl be easy as...lol, i wouldn't stress to much....