Transmission variance between petrol and diesel

[inky_black]

Do you have a source for that data? I wasn't able to find anything....
Thanks!!

I would also like to have the exact data / internal data. I saw the two gearboxes disassembled in a workshop, and I noticed the larger and reinforced components. It is also noticeable in which vehicle classes the different transmissions are usually installed. I also wonder how the ZF 8HP51 is sufficient for a car like the Grenadier. In the weight class, I had even expected the 8HP90 or even the ZF PowerLine, which is a heavy weight 8HP.

 

[TD5-90]

See post #35, or google "ZF 8HP" - plenty of info on these transmissions. As the numbers of the variant go up (8HP51, 8HP55, 8HP70, etc.) they are built to handle more power. I think we can trust Wikipedia on this, but there are other sources if you look.

ZF 8HP transmission - Wikipedia

en.wikipedia.org

Sorry stickshifter, that data is (by far...) not sufficient to evaluate the differences of the 2 transmission versions. At least max input rpm, max output torque and max transmittable power is required.

 

[jrchrds]

Here are two videos that has been shared on the LR forum from a guy i respect around the ZF transmission. The same transmission that is going into the Petrol IG is in the L663.

https://www.youtube.com/watch?v=HhkH3Zc0-Dc&t=373s

https://youtu.be/FqyPizRyphQ

Coming from a manual transmission (the grenadier will be my first auto) what a great video. Some interesting service notes that I took away- having to replace the entire oil pan as the filter is built in, and the method for checking the oil level, and very specific oil requirements.

 

[TD5-90]

I would also like to have the exact data / internal data. I saw the two gearboxes disassembled in a workshop, and I noticed the larger and reinforced components. It is also noticeable in which vehicle classes the different transmissions are usually installed. I also wonder how the ZF 8HP51 is sufficient for a car like the Grenadier. In the weight class, I had even expected the 8HP90 or even the ZF PowerLine, which is a heavy weight 8HP.

Yes, that would be very helpful!
From just looking at the size of the components it is impossible to judge performance. At most, one can tell that the torque is probably higher with larger wheels and clutches, but not the power!

 

[DaveB]

Coming from a manual transmission (the grenadier will be my first auto) what a great video. Some interesting service notes that I took away- having to replace the entire oil pan as the filter is built in, and the method for checking the oil level, and very specific oil requirements.

My local BMW Service specialist said don't follow BMW service intervals.
Oil needs to be changed much more frequently

 

[jrchrds]

My local BMW Service specialist said don't follow BMW service intervals.
Oil needs to be changed much more frequently

It's a little early, but what is the recommended interval for these transmissions?

 

[Tazzieman]

It's a little early, but what is the recommended interval for these transmissions?

Depends upon driving style , loads e.g. towing etc.

 

[Jean Mercier]

My local BMW Service specialist said don't follow BMW service intervals.
Oil needs to be changed much more frequently

I have always known that official dealers or service companies push maintenance intervals, they earn money on it.
Car manufacturers will advice maintenance periods according to the market, but always with a safety margin.
Leasing companies will always lengthen the maintenance intervals, because after year 4 (in Belgium at least) they sell the car.

The maintenance manual of my Suzuki Grand Vitara says: oil change every 20000 km. My service company always puts a sticker: 15000 km.
I change oil between 20000 and 25000 km because I have a lot of motorway (highway) trips (hate it). The reals 4X4 or heavy mountain is limited to less than 500 km a year I guess (and I love it).

My car is 10 years old and has some 210000 km. Motor hasn't been a problem.

 

[DaveB]

recommended is 30,000kms but I think he said 10 or 15,000 kms is best

 

[jrchrds]

I have always known that official dealers or service companies push maintenance intervals, they earn money on it.
Car manufacturers will advice maintenance periods according to the market, but always with a safety margin.
Leasing companies will always lengthen the maintenance intervals, because after year 4 (in Belgium at least) they sell the car.

The maintenance manual of my Suzuki Grand Vitara says: oil change every 20000 km. My service company always puts a sticker: 15000 km.
I change oil between 20000 and 25000 km because I have a lot of motorway (highway) trips (hate it). The reals 4X4 or heavy mountain is limited to less than 500 km a year I guess (and I love it).

My car is 10 years old and has some 210000 km. Motor hasn't been a problem.

My 2004 tacoma (350k miles/563k km) gets 5k mile/8k km oil changes and 15k mile transmission/diff oil changes and the only major damage I've ever had was when the wife swam it and didn't tell me. Toyota's stock breather scheme allowed water into the transmission via the breather, which eventually ruined the 1st gear synchro gear. I ask because the ZF 8HP factory oil change interval is 50-75k miles (81-120k km). I'm curious to hear what @DaveB's friend had to say about shortening that interval.

 

[Jean Mercier]

recommended is 30,000kms but I think he said 10 or 15,000 kms is best

Use the recommended and lower it when your really think the car has suffered a lot! That is what I do.
Oils became better, motors also, ...
How old is your specialist? Probably as old as me, and he remembers the Peugeot 504 (my father owned two)

 

[stickshifter]

Sorry stickshifter, that data is (by far...) not sufficient to evaluate the differences of the 2 transmission versions. At least max input rpm, max output torque and max transmittable power is required.

Got it. I was probably thinking of other posts on this topic, in which people didn't know that there were different variants of transmissions between the B57 and B58, so I was just pointing out that the diesel one can handle more torque than the gasser. Why are you looking for those specifications? Will this data be a factor in you deciding between the B57 and B58? Are you planning on tuning either of those engines?

 

[DaveB]

My 2004 tacoma (350k miles/563k km) gets 5k mile/8k km oil changes and 15k mile transmission/diff oil changes and the only major damage I've ever had was when the wife swam it and didn't tell me. Toyota's stock breather scheme allowed water into the transmission via the breather, which eventually ruined the 1st gear synchro gear. I ask because the ZF 8HP factory oil change interval is 50-75k miles (81-120k km). I'm curious to hear what @DaveB's friend had to say about shortening that interval.

Not a friend
I rang 3 BMW dealers to find out what a service would cost on that engine gearbox combo nd none could answer me.
I then rang this local specialist service mechanic and he told me
Also said the diesel and petrol cost the same to service.

 

[stickshifter]

My local BMW Service specialist said don't follow BMW service intervals.
Oil needs to be changed much more frequently

And how frequently will be related to how hot you run it. Heavy towing in hot weather is probably the biggest assault on transmission oil, but stop & go driving is also bad. Its also tough on a transmission to shift between forward and reverse if the vehicle is moving. But I've only owned manual transmissions, so take that with a grain of salt...

 

[ADVAW8S]

ZF recommends a transmission oil change every eight years or 50,000 miles, and that's a job you can tackle at home. For this DIY, we are using a service kit for BMWs. Although the kit is for the BMW 8HP45 and 8HP70, you can apply the same basic process to servicing every ZF 8-speed, regardless of the make and model.Oct 18, 2021

 

[DaveB]

And how frequently will be related to how hot you run it. Heavy towing in hot weather is probably the biggest assault on transmission oil, but stop & go driving is also bad. Its also tough on a transmission to shift between forward and reverse if the vehicle is moving. But I've only owned manual transmissions, so take that with a grain of salt...

Pretty sure you have to have your foot on the brake before you can go into drive or reverse in ZF transmissions

 

[stickshifter]

My local BMW Service specialist said don't follow BMW service intervals.
Oil needs to be changed much more frequently

That's good that your BMW tech is already thinking that regular BMW service intervals may not apply to the Grenadier. Unlike Mercedes, Jeep, Ford, Ram, and other makers of heavy duty vehicles, BMW doesn't make a vehicle like the Grenadier (which is why - presumably - they agreed to let Ineos use their engines). There may be a bit of a learning curve in the BMW service centers.

If they offer to lower the vehicle, set it up on 22-inch wheels and racing slicks, and tune the engine to 1000 HP, consider taking your vehicle elsewhere for service

 

[TD5-90]

Got it. I was probably thinking of other posts on this topic, in which people didn't know that there were different variants of transmissions between the B57 and B58, so I was just pointing out that the diesel one can handle more torque than the gasser. Why are you looking for those specifications? Will this data be a factor in you deciding between the B57 and B58? Are you planning on tuning either of those engines?

No and No. I already have decided for the diesel, and I don't plan to tune. And must admit that I rather would have had a manual transmission...

(Only) reason is I think that the discussion here could eventually be more fact-based / engineering like.

 

[stickshifter]

Pretty sure you have to have your foot on the brake before you can go into drive or reverse in ZF transmissions

How much I know about auto transmissions:

 

[DaveB]

How much I know about auto transmissions:
View attachment 7799873

I have driven pretty much every kind of car transmission
Manuals

• 3 on the tree
• 4 speed column shift
• 5 speed column shift
• 4 on the floor
• 4 on the floor plus switched overdrive on top
• 5 on the floor
• 6 on the floor
• 8 speed with a forward and reverse lever

Auto

• 3 speed column shift
• 3 speed push button on dash
• 3 speed on floor
• 4 speed on floor
• 7 speed on floor
• 5 speed semi auto
• 6 speed sequential
• 7 speed paddle shift

I love driving a manual - occasionally now.
Too tiring now in heavy traffic
Auto is arguably better in many offroad situations
It is good that Ineos have made the manual over ride a complete hold.
I think it will only change if you come to a stop
My auto box does the same in my current car.
Changes back to first if you stop