TheSamba.com :: View topic - GL 4 or GL 5

Mon May 13, 2024 8:14 pm

I only had one finger smear of metal smug on the mag drain plug after 49'800 miles of off road and street driving. I would say the Valvoline did a damn good job. If your trans doesn't shift right its wore out, rebuilt wrong, bad shift bushing/coupler, not adjusted/shimmed right on the tunnel or adjust your clutch cable.

Mon May 13, 2024 11:41 pm

DesertSasquatchXploration wrote: I only had one finger smear of metal smug on the mag drain plug after 49'800 miles of off road and street driving. I would say the Valvoline did a damn good job. If your trans doesn't shift right its wore out, rebuilt wrong, bad shift bushing/coupler, not adjusted/shimmed right on the tunnel or adjust your clutch cable.

I had a fresh rebuild that shifted just fine with a fill of GL-4 and after a break in period I did a drain and refill using the oil Gears is recommending, the shifting instantly went to crap so it got drained after only a few dozen miles, but wouldn't shift well again when refilled with GL-4, a route I had sadly been down before. I tried running Swepco 201, a 5W40 oil, then a Valvoline synthetic ATF, and finally a tractor hydraulic oil to get an acceptable shift. Its a bit noisier with the hydraulic oil in the box, but at least its not a PITA going through the gears. I forced in an extra quart of oil when I went to the hydraulic oil and suspect I will get a decent enough life out of the box that way.

Tue May 14, 2024 7:02 am

I just changed the gear oil in my 1971 VW, my 1988 Mazda truck, my 1998 Frontier, and my 2004 Frontier (all 4-cylinder, manual transmissions). I used Ultra1Plus GL-4 gear oil purchased through Amazon. Previously in my Mazda truck I used Sta-Lube GL-4 purchased at NAPA, but the Ultra1Plus is less expensive.

I also did the rear differential gear oil on those 3 trucks.

When I installed my rebuilt MoFoCo transmission into my 1970 VW back in 2018, I added the gear oil, but did not record which brand.

Thu May 16, 2024 3:28 pm

Cusser wrote: I used Ultra1Plus GL-4 gear oil purchased through Amazon. Previously in my Mazda truck I used Sta-Lube GL-4 purchased at NAPA, but the Ultra1Plus is less expensive.

I would like to see how both the Sta-lube and the Ultra1plus did in standard wear test.

Sun Jul 14, 2024 8:50 pm

I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

Mon Jul 15, 2024 6:39 am

'64cal lookdub wrote: I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

The controversy seems to be the effects over time using the 'wrong' lube.

Mon Jul 15, 2024 7:32 am

scottyrocks wrote: '64cal lookdub wrote: I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

The controversy seems to be the effects over time using the 'wrong' lube.
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.

Mon Jul 15, 2024 7:48 am

'64cal lookdub wrote: scottyrocks wrote: '64cal lookdub wrote: I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

The controversy seems to be the effects over time using the 'wrong' lube.
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Please list their names or quote their posts.

Mon Jul 15, 2024 8:07 am

After finding out that Ford used ATF in the Escort manual gear box I swapped the gear lube out in my Rabbit for ATF. I did it in the winter and the result was instantaneous. It shifted just like summer! The second thing was that the engine no longer had a tendency to stall on cold start up when letting the clutch out for the first time in the morning.

Initially I was going to change back to regular gear oil for summer but I never did. I beat on that transaxle for the next 6 years with 15+ psi of boost and as far as I know there was no issues. The transaxle has not been out yet for any reason.

I am not sure if ATF would work with our Hypoid final drive gears in air cooled VWs. I have not tried it.

Mon Jul 15, 2024 8:18 am

My 84 Accord used ATF in the manual gearbox.

Mon Jul 15, 2024 9:38 am

Glenn wrote: '64cal lookdub wrote: scottyrocks wrote: '64cal lookdub wrote: I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

The controversy seems to be the effects over time using the 'wrong' lube.
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Please list their names or quote their posts.
Waste of time, my point was I put GL5 in after draining GL4 and it shifted exactly the same.

Mon Jul 15, 2024 12:50 pm

'64cal lookdub wrote: Glenn wrote: '64cal lookdub wrote: scottyrocks wrote: '64cal lookdub wrote: I recently filled one of my cars with cheapo $20 Supertech 80w90 GL5. I didn’t notice a shifting difference from the Sta Lube GL4. $85 a gallon for Sta Lube now is ridiculous.

The controversy seems to be the effects over time using the 'wrong' lube.
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Please list their names or quote their posts.
Waste of time, my point was I put GL5 in after draining GL4 and it shifted exactly the same.
Great... I found that out 15 years ago. Welcome to the club.

Fri Jul 26, 2024 3:37 am

'64cal lookdub wrote:
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Only one guy made that claim.

Fri Jul 26, 2024 3:39 am

oprn wrote: After finding out that Ford used ATF in the Escort manual gear box I swapped the gear lube out in my Rabbit for ATF. I did it in the winter and the result was instantaneous. It shifted just like summer!
You can say the same thing when you switch from 80W-90 to 75W-90. One of my transmissions has 70W-85 in it.

Fri Jul 26, 2024 6:59 am

Glenn wrote: My 84 Accord used ATF in the manual gearbox.
My 1975 Chevy Luv used 30W engine oil in its manual transmission.

Fri Jul 26, 2024 7:46 am

Bruce wrote: '64cal lookdub wrote:
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Only one guy made that claim.
Let's stone him.

Fri Jul 26, 2024 9:02 am

Glenn wrote: Bruce wrote: '64cal lookdub wrote:
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Only one guy made that claim.
Let's stone him.

I have made that claim as have others, way more than one. What I am still waiting on is for Bruce to show me a gear set that was harmed by a GL-4 that is recommended for use in a transaxle with low offset hypoid gears.

Fri Jul 26, 2024 9:22 am

Wildthings wrote: Glenn wrote: Bruce wrote: '64cal lookdub wrote:
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Only one guy made that claim.
Let's stone him.

I have made that claim as have others, way more than one. What I am still waiting on is for Bruce to show me a gear set that was harmed by a GL-4 that is recommended for use in a transaxle with low offset hypoid gears.
Generally when a product is superseded the old product doesn't instantly become obsolete.

For example, most spark plug manufacturers have switched to resistor spark plugs. Using non-resistor plugs will not harm the engine.

Use whatever you like... doesn't matter to me.

Fri Jul 26, 2024 2:42 pm

Glenn wrote: Wildthings wrote: Glenn wrote: Bruce wrote: '64cal lookdub wrote:
Yea but a few have claimed their cars “instantly” shifted bad/worse with GL5.
Only one guy made that claim.
Let's stone him.

I have made that claim as have others, way more than one. What I am still waiting on is for Bruce to show me a gear set that was harmed by a GL-4 that is recommended for use in a transaxle with low offset hypoid gears.
Generally when a product is superseded the old product doesn't instantly become obsolete.

For example, most spark plug manufacturers have switched to resistor spark plugs. Using non-resistor plugs will not harm the engine.

Use whatever you like... doesn't matter to me.

VW recognized that a GL-5 oil, like what they used in the final drives of the automatics could cause problems with the synchros in the manual gear boxes and thus specced GL-4. An oil that carries a GL4 & Gl-5 oil is a GL-5 oil for all intents and purposes and today may well carry a MT-1 rating indicating they are designed for non sychronized gear boxes and should not be used in a sychronized box.

As I have posted before, today's GL-4 oils give similar 4 ball wear test results to what comparably priced GL-5 oils do, so there is little or nothing to be gained by running a GL-5 oil.

Fri Jul 26, 2024 3:54 pm

Bruce wrote: oprn wrote: After finding out that Ford used ATF in the Escort manual gear box I swapped the gear lube out in my Rabbit for ATF. I did it in the winter and the result was instantaneous. It shifted just like summer!
You can say the same thing when you switch from 80W-90 to 75W-90. One of my transmissions has 70W-85 in it.
No I don't think that is entirely true. There may be a small noticeable difference but in my case the change was huge. ATF is a completely different animal from 75w90! Living on the coast as you do perhaps you have never felt how stiff transmission oil can get in the winter.