Mk5 VW Golf 1st > 2nd shift grind when cold.

[BLKGTTDI]

I drive a Mk5 Golf GT TDI 140 with a 6 speed gearbox. I am using the correctly specified gearbox oil only recently changed which is G 052 171 A2.

I am suffering from a grinding gear change from 1st to 2nd gear ONLY WHEN COLD after 20 mins driving the gearchange is absolutely fine, in fact the gearbox feels completely different when warmed up, it's heart breaking to start up the following day only for it to grind 1st to 2nd again.

I have done a TON of research on this and it seems that many with notchy/grinding shifts have reported great success using alternate gearbox oils like GM or Pennzoil Synchromesh.

As my issue is only an issue from cold I'd like to try a different gear oil before I spend big bucks to have a new syncro installed, so please can you let me know if you have any suggestions?

Thicker or thinner oil?

Has anyone tried any of the synchromesh oils in their 6 speed gearbox with success? (GM/AC Delto, Pennzoil Syncromesh etc)

The specified VW oil is G 052 171 A2 which is fully synthetic 70W-75 (6.5 cSt)

Many people reporting much better shifts using Pennzoil Synchromesh which I believe is a mineral oil 75W-80 (9.3 cSt)

Is there any reason why Pennzoil Synchromesh spec would help a gearbox with tired synchros shift better in the cold?

Many regards.

 

[slug_bug]

Miata owners like to use synthetic Motorcraft fluid in their 6 speed gear boxes to smooth out cold weather shifts.

Ford synthetic transmission fluid (XT-M5-QS)

Redline MT-90 is another popular choice.

I use the motorcraft in my 6 speed and it definitely made a positive difference during cold Michigan winters.

 

[Trav]

I am running Pennzoil Synchromesh in a VW 5 spd. It didn't grind but was hard to shift into second when cold.
This stuff cured it right away, 0f and it shifts smooth. Some people claim its too thin, it isn't.
One reason cited is the differential needs something heavier and recommend (wrongly IMHO RL or Amsoil MTF, both suck in these units it doesn't help). How many automatic transaxles use a separate diff fluid fill?
Very few, they use the ATF and live happily.

I would try the GM stuff, i think you will like the results.

 

[antiqueshell]

Originally Posted By: BLKGTTDI
I drive a Mk5 Golf GT TDI 140 with a 6 speed gearbox. I am using the correctly specified gearbox oil only recently changed which is G 052 171 A2.

I am suffering from a grinding gear change from 1st to 2nd gear ONLY WHEN COLD after 20 mins driving the gearchange is absolutely fine, in fact the gearbox feels completely different when warmed up, it's heart breaking to start up the following day only for it to grind 1st to 2nd again.

I have done a TON of research on this and it seems that many with notchy/grinding shifts have reported great success using alternate gearbox oils like GM or Pennzoil Synchromesh.

As my issue is only an issue from cold I'd like to try a different gear oil before I spend big bucks to have a new syncro installed, so please can you let me know if you have any suggestions?

Thicker or thinner oil?

Has anyone tried any of the synchromesh oils in their 6 speed gearbox with success? (GM/AC Delto, Pennzoil Syncromesh etc)

The specified VW oil is G 052 171 A2 which is fully synthetic 70W-75 (6.5 cSt)

Many people reporting much better shifts using Pennzoil Synchromesh which I believe is a mineral oil 75W-80 (9.3 cSt)

Is there any reason why Pennzoil Synchromesh spec would help a gearbox with tired synchros shift better in the cold?

Many regards.


Sorry to say but do you trust the shop that changed the fluid?
Did they use the correct fluid or use something that is
suitable for that spec? What does the repair order say with regard to the fluid they used, it is NOT uncommon at all for any shop to use something that is NOT the specificed fluid and tell you they did anyhow. DID YOU HAVE THE 1st to 2nd grind before you had the fluid changed?

I would bet the original fluid is either Castrol Syntrans FE 75w
or Pentosin MTL2. They are very similar fluids and both are
fully synthetic. I would definitely take the car back if the grinding started after the changed fluid and tell them they need to use either of the fluids I mentioned here. DO NOT USE A GL-5 spec fluid! Only a GL-4 spec both fluids I mentioned above meet VW
requirements and are likely the OEM fluids for most of that model run.

 

[aquariuscsm]

Will thinner than fluid spec fluid destroy the bearings? I'd just shift gently till it's warmer up thus keeping the spec'd fluid.

 

[antiqueshell]

Originally Posted By: aquariuscsm
Will thinner than fluid spec fluid destroy the bearings? I'd just shift gently till it's warmer up thus keeping the spec'd fluid.


Actually the VW spec fluid is about a thin as you can get
for any manual gearbox and it is probably fully synthetic as well.
The Pennzoil Synchromesh is actually thicker than factory spec...

If my hunch is correct the OP didn't start having a problem until his shop replaced the OEM fluid..they claim they replaced with the same spec but I would bet that they did NOT.

I would go back to the shop and have them replace with the OEM fluid
(watch them pour from the factory bottles, or use one of the OE fluids I mentioned in my earlier post, again I bet the shop screwed him whether by accident or intentionally by using an incorrect fluid.

 

[antiqueshell]

An alternative would be Shell Spirax S4 G, a fully synthetic
GL-4 spec fluid that would also be easy to find in the UK.
If you have the misfortune to live in the USA it is almost
impossible to find this or the Castrol Syntrans FE 75w

 

[badtlc]

Pentosin MTF2 has the best cold weather specs you are going to find. You can get 5L jug on Amazon for a good price.

 

[antiqueshell]

Originally Posted By: badtlc
Pentosin MTF2 has the best cold weather specs you are going to find. You can get 5L jug on Amazon for a good price.


Agreed. I don't know what the situation is in the UK but I would
figure that Pentosin MTL2 is readily available if not the cheapest.
The Castrol Syntrans FE 75w is pretty close in specs (almost as good as the Pentosin MTL2) and is also a good alternative.

 

[MolaKule]

I think antiqushell may have hit upon a possible reason for poor shifting.

Are you absolutely sure they put the correct viscosity fluid in the transmission?

The folowing MTL fluids should be compatible to the VW G 052 171 A2:

Castrol Syntrans FE 75W,

BMW (Pentosin) MTF-LT-3,

Honda MTII or MTF 2.

Ford FML-XT-11-QDC

Volvo Manual Transmission Fluid (6.4 cSt) [Recommended for: type M65 5-speed with 6-cyl. engine, M66, MTX75 and MMT6 and of the type M56, M58 and M59 from and including model year 1996. Meets Ford specification WSSM2C200-D2]

 

[BLKGTTDI]

Thank you everyone for your comments. Yes I know for definitely that the VW specified G052 171 A2 was used as I bought the stuff myself from VW and a mechanic friend of mine did the fill.

 

[Olas]

Redline MTL

 

[badtlc]

Originally Posted By: Olas
Redline MTL

Good fluid but much thicker than OEM fluid.

 

[BLKGTTDI]

Originally Posted By: Trav
I am running Pennzoil Synchromesh in a VW 5 spd. It didn't grind but was hard to shift into second when cold.
This stuff cured it right away


Originally Posted By: badtlc
Pentosin MTF2 has the best cold weather specs you are going to find.


These are the two oils I'm interested in trying.

I read more about the Pentosin here
http://www.ft86club.com/forums/showthread.php?t=16604

My VW specified fluid is 70W-75 (6.5cSt)

According to MolaKule superb viscosity list

Pentosin MTF2 - 75W-80 (7.5 cSt)
Pennzoil Synchromesh - I believe is 75W-80? 9.3 cSt

Let me explain a little more.

My first ever 1st > 2nd shift in the morning no grind

Literally it's from the second 1st > 2nd that the grind starts and continues for 15/20 minutes till car warms up.

So, 1st > 2nd is fine on first ever 1st > 2nd of the day when there's minimal oil in the gears/syncs. And when the cars warm.

From this I glean that the problem is the cold performance on the VW oil?

Based on this, and the specs of the Pentosin & Pennzoil, which should I try first!?

 

[badtlc]

Pentosin is made of unicorn tears or something because it has the lowest pour point I have ever seen at -76F! The synchromesh comes nowhere close to that.

I had never seen a 70W-75 spec before. That is interesting. You should probably look into some DCT fluids if that is the case.

 

[BLKGTTDI]

Originally Posted By: badtlc

I had never seen a 70W-75 spec before. That is interesting. You should probably look into some DCT fluids if that is the case.


It maybe a 75 based on this
http://www.fuchslubricants.com/titan-sintofluid-fe-sae-75w

 

[Trav]

I tried both the Redline and the Amsoil in these units and it just sucks there is no other way to say it. It shifts harder cold than a 90 yr old with arthritis, its seems way too thick for these units.

Sorry i just noticed you are in the UK, so you have a lot of good options open to you.
The Castrol, Fuchs, are both good, i would try either of these.
Notice the Fuchs even covers the old VW spec G 052 726 A2 with a 75w fluid. Some guys on Bitog were ranting that the Pennzoil is too thin.

 

[BLKGTTDI]

I believe the VW G 052 726 A2 specified for my car is thinner than Pennzoil.

6.5cSt versus 9.3 cSt

 

[BLKGTTDI]

Originally Posted By: badtlc
Pentosin is made of unicorn tears or something because it has the lowest pour point I have ever seen at -76F!


I'm interested in this.

I believe the VW G 052 726 A2 specified for my car is 6.5 cSt@100

The Pentosin is 7.5 cSt@100C

Please excuse my ignorance.. How would the thicker Pentosin flow easier than the thinner VW fluid?

Sorry, just trying to figure this all out

Thanks!

 

[Greasymechtech]

Thicker at 212F temp still leaves other fluid temp measurements unknown(100F, 70F, 40F, 0F, -40F..). Viscosity index, base oils used, VII or VM used, PPD's, will affect fluid capability at other temps.

Double clutch that grinding shift.

Its worth a try to fill it with the Pentosin, Comma, or Ravenol, Synchromesh, Castrol BOT or Syntrans, ... fluids. Rebuild the trans or trial/error with several fluids until you find one that improves the shift.

A 50w glue on timer and heater is another option.