NC 6spd 5th gear grind

[ilovemassageparlours]

Hi all,

Just started getting a 5th gear grind, when shifting into it @ 3k rpm or higher.

the car is at 106,000kms (purchased at 100,000km).

Going to punt and say its the synchro.

Will it be worth bleeding and putting in Ford Motorcraft before i start looking at ebay for another transmission?

Any other opinions or cost effective solutions before jumping the gun?

Thanks!

[bruce]

Which option is cheaper.....

[ilovemassageparlours]

What options should I look at before assuming the gearbox should be replaced?

Could a slave/master cylinder cause this or anything else?

Should I continue as it is and take a little more precaution when shifting into 5th or look for a gearbox straightaway.

[Regie]

the Motorcraft oils can't be bought over here, you will need to import from the states

Our equivalent is Nulon GL4 gearbox oil, same spec and a fair few of us have had great results from that.

If its still running the factory clutch it could be close to worn out.

The slave/master cylinders are pretty reliable on the NC, compared to earlier models. My car has just over 110k kms and hasn't skipped a beat.

[JBT]

The slave/master cylinders are pretty reliable on the NC, compared to earlier models. My car has just over 110k kms and hasn't skipped a beat.

Same here....including a fair bit of track and hill climb work.

[Mr Morlock]

The simplest cheapest thing is get a mechanic to drive the car and they will confirm if its a synchro problem. Synchros normally take sometime to wear out and at 100,000 it suggests some abuse. Many old cars had wretched synchros and drivers simply slowed their changes or technique but its hard not to drive a sports car in an sporting way. Replacing a gearbox is not going to be cheap and a second hand one might not be any better. There is advice on Redline oil as well but not sure if that is a good idea or not.

[Charlie Brown]

214,000 klm on my box and zero syncro problems.
Bet the previous owner put GL5 oil in the box. Swap it out with Nulon GL4 full synthetic oil and report back.

[ilovemassageparlours]

Thanks guys, will look for Nulon gl4 75w 90 GL4.

5th gear stopped crunching....but gear 2 feels alot worse lately.

[ilovemassageparlours]

Im guessing the Nulon oil used is the 75w-85?

Can't seem to find Nulon in GL4 @ 75w-90.

[JBT]

Im guessing the Nulon oil used is the 75w-85?

Yep, that's the one.