TD4 Crunching into third gear! :(

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Alibro

Well-Known Member
Posts
7,182
Location
Northern Ireland
Hi guys
Some of you may have been following my latest project (Audrey). I've been having fun working away at VCU, windows, speakers and a few other things and tonight took her out for a test drive. That was when I remembered the drive home after buying her, I didn't notice anything during the test drive but on the drive home I noticed a crunch when changing into third gear. It doesn't do it every time and is worse when changing down from fourth or if changing quickly. It doesn't crunch into any other gear and the clutch is fine so I'm concerned it is the gearbox itself.
I've searched for other threads with similar issues but could only find one and it didn't give me an answer. I believe the clutch was replaced in the past (it has a tow barso may have been used for towing) and I notice the plate on the bulkhead flexes a bit when I change gear but not sure if any of that matters.

Have to say it was a big downer when I realised/remembered the issue as I really don't fancy having to replace the gearbox. :(
 
synchro on the way out ??
That was my worry.
First thing is to change the box oil. ;)
I was going to change the oil anyway then saw in the service history it has already been done so wasn't going to bother, I guess he could have used the wrong oil.
Seems odd the gearbox is stuffed at only 115k but if the clutch has been replaced I guess the user may have damaged the box while the clutch was on it's way out.
I've never had a gearbox/synchro issue in over 30 years driving so it came as a nasty surprise and have to admit I wasn't looking for it during the test drive.
 
Alibro, Hi mate,

This may be very controversial to some but hey :rolleyes: - I lived through the times we did this and little has changed apart from the throw away mentality ;)
Ok, yes it defintiely sounds like 3/4 synchro - problems like this can be caused by the cone wearing or in some cases contamination leading to a build up of crud -

- small question and not really relevant to the proposed remedy attempt - but, what oil is in there now - and also the oil change history with type- do you know for certain ?
Anyway -back to the issue at hand :)

You may have a way to 'correct' the issue - temporarily or long term.

Now, this is 'old school' but worked /works well - and - you have nothing to lose really.

What we used to do on the rally cars if we had a synchro issue as you describe was this -

Drain the box ! - (if not full of metalic crap - then- )- now, refill with ATF !! (YES - ATF!)- any will do - drive it for around 100 miles or so - not motorway - town driving with lots of changes, then drain and refill with MTF94, or 10W40., - if you get a good result - and 10W40 is fine afterwards - simply change it every 40 or 50 k

This was the standard way of cleaning out clogged synchros on Rally cars (and I still use it) and it worked well on my freeby with a small 'second / third 'chink'. - now cured completely ! - Obviously, if the synchro is actually $hagged - it will still be $hagged at the end of the 'cleaning process'- then hey - nothing lost - but, many a 'snicking' box has been brought back to good life this way.. the Getrag 5 speed in the Chevette and the rocket box or ford boxes were often treated to this with superb results. - we did this in the service intervals on a 'selective' (Stage) if issues were reported ! :oops:

It is like 'gunk' for your gearbox, but with suitable lube qualities.
Just a trick of the trade - old school - that works well in most cases. - not all obviously - it depends on your issue internally and also the history of the oils used - often mixtures of oils over the years can cause problems.

Enjoy and I hope it helps. - again nothing to lose.

One from 'me little black book'

Regards and wish you well .
Joe;)
 
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Thanks for that Joe, really appreciate giving me hope I might not have to change it. I have no way of knowing what oil is in the gearbox so my plan is to change with MTF94 and try it.
A mate suggested Slick50, what do you guys think? If worth a try it could be done before trying the ATF as the gearbox will have new oil in it anyway.
 
Thanks for that Joe, really appreciate giving me hope I might not have to change it. I have no way of knowing what oil is in the gearbox so my plan is to change with MTF94 and try it.
A mate suggested Slick50, what do you guys think? If worth a try it could be done before trying the ATF as the gearbox will have new oil in it anyway.
ATF is a powerful cleaning agent and will clean and crud out of the tiny oil stripper grooves. This can improve shift quality, if dirt is causing the issue. I'm not sure what spec oil is needed for the Freelander box but gearboxes with brass / bronze synchro rings or selector forks must not use a GL5 oil as it breaks the bronze down.
Oh and don't use Slick50. It's a snake oil at best and damaging at worst.
 
Top job boys! New oil to try it first then and if still crunching ATF for a hundred or two miles it is.
Unless that is I see lots of nasty stuff when changing the oil.
 
Hi Joe

I had an XR3i back in the good old days (early 90's) - had 3rd gear synchro problems almost from new.
Did Ford have box quality issues then ??

thanks
John



Alibro, Hi mate,

This may be very controversial to some but hey :rolleyes: - I lived through the times we did this and little has changed apart from the throw away mentality ;)
Ok, yes it defintiely sounds like 3/4 synchro - problems like this can be caused by the cone wearing or in some cases contamination leading to a build up of crud -

- small question and not really relevant to the proposed remedy attempt - but, what oil is in there now - and also the oil change history with type- do you know for certain ?
Anyway -back to the issue at hand :)

You may have a way to 'correct' the issue - temporarily or long term.

Now, this is 'old school' but worked /works well - and - you have nothing to lose really.

What we used to do on the rally cars if we had a synchro issue as you describe was this -

Drain the box ! - (if not full of metalic crap - then- )- now, refill with ATF !! (YES - ATF!)- any will do - drive it for around 100 miles or so - not motorway - town driving with lots of changes, then drain and refill with MTF94, or 10W40., - if you get a good result - and 10W40 is fine afterwards - simply change it every 40 or 50 k

This was the standard way of cleaning out clogged synchros on Rally cars (and I still use it) and it worked well on my freeby with a small 'second / third 'chink'. - now cured completely ! - Obviously, if the synchro is actually $hagged - it will still be $hagged at the end of the 'cleaning process'- then hey - nothing lost - but, many a 'snicking' box has been brought back to good life this way.. the Getrag 5 speed in the Chevette and the rocket box or ford boxes were often treated to this with superb results. - we did this in the service intervals on a 'selective' (Stage) if issues were reported ! :oops:

It is like 'gunk' for your gearbox, but with suitable lube qualities.
Just a trick of the trade - old school - that works well in most cases. - not all obviously - it depends on your issue internally and also the history of the oils used - often mixtures of oils over the years can cause problems.

Enjoy and I hope it helps. - again nothing to lose.

One from 'me little black book'

Regards and wish you well .
Joe;)
 
Hi Joe

I had an XR3i back in the good old days (early 90's) - had 3rd gear synchro problems almost from new.
Did Ford have box quality issues then ??

thanks
John
Hi John,
Ford were no worse than any others really - in fact pretty damn good, the XR3i was a pretty good unit. I suspect it was actually faulty from new. The dealer should have replaced it.
Apart from the A series 'Mini' - which we tended to use straight cut gear sets in (and of course run the exact same oil as the engine as the gearbox is in fact a pseudo sump - yet were damn reliable when used with a centre pick up to stop oil bias to one side on cornering!)) All the boxes we worked on were rear wheel drive and they were incredibly reliable and strong. We used to use a modified ford casing with an Austin 1800 gear set on some special units and BMW Getrag boxes on many others which apart from occasional 2/3 synchro were amazing - these were being completely hammered though with 'bang' changes (racing changes). The box standard ford RWD gearbox and 'standardescort van' 4.4 diff unit were used in many many a rally car with incredible reliability. but I digress. :)
Ford FWD units were very good really.
 
Top job boys! New oil to try it first then and if still crunching ATF for a hundred or two miles it is.
Unless that is I see lots of nasty stuff when changing the oil.
Hi mate,
Just to add re the 'slick 50' - as Nodge says - 'snake oil' as are 99.9 percent of any lubricant 'additive' -even many 'semi synthetic' and 'fully synthetic' oils may not perform any better than a plain mineral oil with additives developed over nearly 100 years.
Slick 50 is a fairly nasty thing to add to anything - it's ptfe base is better used in frying pans where it does not clog small oil ways and doesn't adhere to anything very well.

You use 10W40 motor oil in the freeby gearbox if you want (it is same spec as 75W90 gear oil) - using a lighter oil in a 'box' is only really an issue if the diff is in the box - which it isn't in the freeby - it is in the IRD.
 
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Hoping to change the oil today so when I see what comes out I'll have a better idea. If full of bits of metal filings I'll be looking for a new gearbox but hopefully not.
The car isn't on the road yet so no big panic.
I was wary of Slick50 but when someone suggests it you always think Maybe.
 
Hi mate,
Just to add re the 'slick 50' - as Nodge says - 'snake oil' as are 99.9 percent of any lubricant 'additive' -even many 'semi synthetic' and 'fully synthetic' oils may not perform any better than a plain mineral oil with additives developed over nearly 100 years.
Slick 50 is a fairly nasty thing to add to anything - it's ptfe base is better used in frying pans.
I actually tested Slick 50 myself in a Ford CVH engine mounted on a test bed in circa 1990. I ran the engine for 10 hours at varying speeds while monitoring coolant temperature, oil temperature, and oil pressure. I noticed no difference in running temperature or oil pressure/ temperature after the Slick 50 was added. After the engine was run for 10 hours, it was stripped for examination. I found no evidence of any kind of coating anywhere on the engine bearings or other wearable components. This would suggest that these additives are simply snake oils. The claims that the coating remains after the oil is drained are highly dubious.
There is some evidence that Teflon in engine oils can provide some protection in certain circumstances however. If I need a guaranteed lubricant on hard to lube area's, I simply use a Molybdenum grease. Molybdenum is what CV joints are lubricated with and will keep lubricating in extremes of pressure. Unlike Teflon, it is a known, tried and tested friction modifier. I also use Moly in my Freelander IRD and rear diff as an extra level of protection. Moly MUST NOT be used in a gearbox however.
 
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The mate who advised me to try Slick50 is a tad gullible so he probably heard (from a salesman) it is good stuff and believed it.
I tend to think if it were that good the oil manufacturers would copy it so all oils would be just as good. The fact they don't rings alarm bells with me.
 
I actually tested Slick 50 myself in for CVH engine mounted on a test bed in circa 1990. I ran the engine for 10 hours at varying speeds while monitoring coolant temperature, oil temperature, and oil pressure. I noticed no difference in running temperature or oil pressure/ temperature after the Slick 50 was added. After the engine was run for 10 hours, it was stripped for examination. I found no evidence of any kind of coating anywhere on the engine bearings or other wearable components. This would suggest that these additives are simply snake oils. The claims that the coating remains after the oil is drained are highly dubious.
There is some evidence that Teflon in engine oils can provide some protection in certain circumstances however. If I need a guaranteed lubricant on hard to lube area's, I simply use a Molybdenum grease. Molybdenum is what CV joints are lubricated with and will keep lubricating in extremes of pressure. Unlike Teflon, it is a known, tried and tested friction modifier. I also use Moly in my Freelander IRD and rear diff as an extra level of protection. Moly MUST NOT be used in a gearbox however.
Hi Nodge, nice one.
Moly is fine and DOES coat surfaces well - I would have no issue in Moly in a diff for example - or yes, the IRD where 5 /10K changes are infrequent and unnecessary. Where I have issues (and have had in the past) with Moly based products is in the normal 'engine' as it heavily discolours the oil which outweighs any benefits. The colour of a modern engine oil is so often a guide to its condition. Moly turns everything muddy grey :) ..
We used to paint performance blocks white to easily spot any leaks - from a fresh fill the sight of an apparent sludge slick after moly was not good for the nerves :) ;)
My freeby L series has 220,000 Km on it now - at 210 it was out for a clutch, rear crank bearing and cambelts etc etc etc (easier to remove the lump!) - always run on cheap supermarket oil and changed at 10K Km - like new still -
This was a block internal shot at 209,000 Km - photo is untouched - just as it came out of the car
. crankcase 209000Km.jpg
 
Hoping to change the oil today so when I see what comes out I'll have a better idea. If full of bits of metal filings I'll be looking for a new gearbox but hopefully not.
The car isn't on the road yet so no big panic.
I was wary of Slick50 but when someone suggests it you always think Maybe.
Alibro mate - sorry if I am too late - DON'T change the old oil for new - go straight for ATF ! - the fact that you have the 'chink' means it either need a flush or it is Ker-Nackered - so it would be a waste of oil... the ATF will do ABSOLUTELY no harm -
Hit it with that first for 100 - 200 Km...

Then _ IF _ it helps - go for the 10W40.... if it doesn't help - then go for a new box.
May save you a few bob mate.
Going for the '10W40' first may mask the issue - hit it with the good stuff - 10 year old ATF - Cheapo supermarket malt ! - no buggering about here haha :confused:
o_O

Joe
 
Cheers mate, thanks for that. I was just heading out to the shop to buy the MTF94 so will get the ATF instead. Not sure when I'll be able to report back though as waiting to sell my MGF before insuring the Freeby.
I'm a bit confused though at the idea of using 10W40, I thought MTF94 was closer to 75W80 oil which is a lot thicker. Are you saying to use 10W40 instead and don't use the MTF94?
 
Cheers mate, thanks for that. I was just heading out to the shop to buy the MTF94 so will get the ATF instead. Not sure when I'll be able to report back though as waiting to sell my MGF before insuring the Freeby.
I'm a bit confused though at the idea of using 10W40, I thought MTF94 was closer to 75W80 oil which is a lot thicker. Are you saying to use 10W40 instead and don't use the MTF94?
Hi mate, There is a direct correlation between 10W40 and 75W80, it is all in the numbering system - very confusing ! - the rating system is definitely not the same ! - one cannot compare them side by side.

See wiki here -
https://en.wikipedia.org/wiki/Gear_oil

Also note -
"API viscosity ratings for gear oils are not directly comparable with those for motor oil, and they are thinner than the figures suggest. For example, many modern gearboxes use a 75W90 gear oil, which is actually of equivalent viscosity to a 10W40 motor oil. Multigrade gear oils are becoming more common; while gear oil does not reach the temperatures of motor oil, it does warm up appreciably as the car is driven, due mostly to shearfriction (with a small amount of heat conduction through the bellhousing from the engine block)."

The minor differences are some of the EP (extreme pressure) additives) - however - due to no differential on the PG1 box (it is in the IRD) it is no issue.. so yes - 10W40 Automotive is fine. - IF however - it had a built in DIFF - it may be more of a concern - not to be bit to others :)

Fear not little drooping seat (to quote the Goon Shows) - sheesh - my age is coming out now - - 'tales of old Dartmoor' etc///
 
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