85-140w - Power Loss in light Japanese truck

Status
Not open for further replies.
Joined
Sep 5, 2019
Messages
5
Location
Brisbane Australia
My first post, so hi everyone
smile.gif


I've got an old 1991 FG 4x4 Mitsubishi Canter truck. 3.3l diesel, formerly non-turbo, but now Turbo
smile.gif
. 4.5t truck so even turbo it's still a bit slow with an old 3.3l 4cyl soot chucker. It would be lucky to have 110-120hp

While trying to chase a drivetrain whine on recommendation I changed the Transfer and Diff's to Dino 85-140w (previously Dino 80w90)

However I'm now certain it has lost power, in such a vehicle this is most noticed on hills. Ie the ability hold speed or how much speed one looses.
Am I going crazy or it possible the drag of such thicker lube could be noticeable?

The rear diff is LSD front is opened (and not engaged on sealed roads, so out of the picture).

Manual states

Manual Transmission:
Normal region SAE 80 Warm region: SAE 90 (I'm inAustralia so it certainly can get warm)

Transfer:
Normal region SAE 80 Warm region: SAE 90

Rear LSD:
SAE 90 LS

Front:
Below 40DegC(104f): SAE 90 Above 40degC(104f); SAE:140

I've isolated the diff (driveshafts out, centre handbrake to load gearbox/transfer) and it's not causing the whine. I've also pulled the inspection cover off the transfer and it looks really good inside with no play anywhere so it's likely from the gear box.

It'd like to know fluids should I change to ensuring good protection but also minimising drivetrain loss?

I'm thinking splurging and going full-synth.
Given the above specs I'm guessing a 75w85 or 75w90 full synth LS should cover all components OK and reduce drag losses?

Do Synthetics help with gear whine also, or best to try an additive for that?


Brand availability will vary here as we have a number of local producers that make good products (Penrite, Nulon, Gulf Western etc) though stuff like Castrol is still available.

Thanks
Dan

Here the truck/camper
smile.gif




Capture.JPG
 
Last edited:
Definitely go back to the oem spec W90. I tried a W140 in my 300ZX one time and it caused noticeable drag.
 
welcome2.gif

SAE 90 of the era then would have been in the upper range of between ISO 150 (KV40 of 150 cSt) and ISO 220 (KV40 of 220 cSt) grades .

Depending on brands, a typical 80W90 in Australia would likely come with a KV40 of 135 - 155 cSt which falls on the lower end of spec'ed SAE 90, if not considered out-of-range.

Unfortunately, the drivetrain whine as described demonstrates this viscosity grade is inadequate.

The 85W140 you had ,depending on actual brand, may have KV40 ranging from 250 cSt to say, 360 cSt . Do check what is the actual data sheet KV40 of gear oil in use that gives you a feeling of 'power loss' and pick another gear oil closer to ISO 220.

A typical 75W85 would carry a KV40 ranging from 60 cSt to 70 cSt and IMHO ,is a big no-no in your application.

So is the case with a 75W90 that typically carries a KV40 of 90 -105 cSt.

A 75W140 of typical KV40 of 170 - 175 cSt may be considered, however its shear stability is poor.

I would personally prefer a hard-to-find monograde SAE 110 (KV40 220 cSt) to a common monograde SAE 90 (of KV40 approaching 200 cSt) as both are shear stable.
 
Last edited:
Cheers for the responses.

aquariuscsm , yeah I will be, it needs ever last baby horse it has haha
smile.gif


zeng, the info and detail is great, thanks. I did a bit of a digging on the fluids used so far + other options


Diffs/Transfer:
Nulon 85w140ls Dino with a KV 40 value of 380 , which is beyond even your estimates
(previous Penrite 80w90ls Dino KV40 of 152)

A huge difference, probably explains the power loss.

Gearbox:
Penrite 75w90 SemiSythn with a KV40 of 99



So If I understand you post correctly all the fluids I have in are not really suitable.
Starting at the gearbox, SAE90 is spec'd for warm climates so current fluid (KV40 of 99) falls short?

Researching some products Gulf Western (local producer) seem to offer the best solutions.

They have the following products.

80w90LS Full Synth with a KV of 185
http://www.gulfwestern.com.au/wp-content/uploads/2018/10/Ultra-Clear-Limited-Slip-80W-90-30059.pdf

This seems suitable for the diffs and transfer, would it also be suitable for the gearbox too or would shifting be effected?
I've read that friction modified fluids can cause premature syncro wear and a GL4 is better for gear boxes?

Their GL4 Gearbox full synths are
75w85 with KV69
http://www.gulfwestern.com.au/wp-content/uploads/2015/07/Ultra-Clear-Gear-Oil%C2%AE-75W-85-60050.pdf
or
75w90 with kv100
http://www.gulfwestern.com.au/wp-co...-Clear-Gear-Oil-Low-Vis-75W-90-30056.pdf


They also have a straight 90
LS90 Full Synth KV of 200
http://www.gulfwestern.com.au/wp-content/uploads/2018/10/Diff-Oil-LS-90-30053.pdf


Thanks again.
 
Quote
I've isolated the diff (driveshafts out, centre handbrake to load gearbox/transfer) and it's not causing the whine. I've also pulled the inspection cover off the transfer and it looks really good inside with no play anywhere so it's likely from the gear box.

Pardon my English, you're sure the whine is from the manual transmission gear box (which used 75W90) and not from Differential (which used 80W90 previously)?
 
Last edited:
I'm glad you posted this.

I just had the differential rebuilt in the 1993 240 wagon. (Dana 30) The shop filled it with dino Phillips 66 85W-140. Volvo spec's 80W-90 GL-5.

I am noticing a loss in power. The diff is also considerably quieter. How much of this is from the rebuild and/or the heavier fluid is hard to say.

I'm considering going to 50/50 mix 80W90/85W145 to see if I notice a difference. And then 80W90.

Sam
 
No difference I can discern between 90 and 140 gear oils in the vehicles I've owned over the years.
21.gif
 
Originally Posted by umungus1122
No difference I can discern between 90 and 140 gear oils in the vehicles I've owned over the years.
21.gif



I wish I could say the same thing. I'm not sure what to make of it.
 
I have noticed very minor differences in past vehicles, though thinking back, all were manuals. In automatics I've never been able to tell. IDK if I could tell at the throttle or hillclimbs, but noise would be less and the driveline might feel like it had less sloppiness in it... tighter... less backlash.
 
That Canter looks awesome, in America these are seen more as a box truck. Why does Oz and Japan have all the cool stuff?

To me, a 75W-90 synthetic gear oil is the way to go in Japanese diffs and they need nothing more than that. If you plan on going out beyond the city limits, maybe 75W-140 that's used in Fords might be a better pick.
 
going from OE 75-140 semi syn to 75-90 redline real synthetic in the rear of my 2011 Frontier SV 4WD + the rest of the drivetrain lubes to redline real synthtic netted me about 3MPG!!
 
Interesting insights, it certainly seems I'm not alone in noticing an overly thick gear oil. Probably more pronounced in what is a quite a large diff (more fluid/bigger gears) combined with a heavy vehicle and very little power.

For those interested in the Truck, it was built as a camper back in 1991 and has lived it's life travelling Aus. The camper body is full moulded fibreglass. I bought it for the platform and and have working on it the past year for the aim to rent the house and travel Australia for a couple of years with my dog.

A bunch of spam pics for those interested
smile.gif


[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]
 
Last edited:
The truck is amazing, it looks like it has been well kept and there are some obvious recent additions, the lights obviously. What's the purpose of the screens in front of the windshield? What kind of range do you have on a full tank?

Now about your dog, what is he? We have an 8 year old blue ACD male and a 1 year old red supposedly ACD female. The male is classic cattledog but the female has been a bit of mystery as she sure doesn't look like him but she sure looks like your dog. Her ears are oversize and never stood up but she looks like your guy, same short coat and she even does the same sit up thing completely on her own. Sorry for the side track, awesome truck and dog you've got.
[Linked Image]
 
Cheers.
I'm not sure the forum allows a post long enough to handle all the upgrades, changes and repairs over the past year, haha. Certainly a labour of love. It's individual and different, gets interest when travelling.

Cool dogs.
Striker is a Kelpie/Aussie Cattle//Border Collie mix. His such an awesome travel buddy. Sucks Australia is so restrictive with dogs vs other countries. Partly why the truck, can leave him in it for periods, it handles warm weather pretty well with the MaxxAir fan.
 
With a synthetic oil I'm sure you would be ok with a 75w-140. You have to research the specs. I went through this recently when I went from a 75w-90 to a 75w-140 for my Ford's (140 is what Ford recommends). The cSt difference between a synthetic and conventional 140 are huge. In no way would I put a conventional 140 in my Ford's. Would be like dragging an anchor!

I haven't noticed any additional drag from the 75w-140 synthetic.
 
Last edited:
Jeff, yep on on EP, not that active though. And thanks
smile.gif


An update for those that helped out.

I dropped all drive train fluids (again haha) and went with Gulf Western (Australian) full Synthetic 80w90LS mentioned above across all components (talked to their tech department first to confirm suitability). I can confirm that running mineral 80w140 does impact performance, probably most noticeable because has so little power already. More interesting is the noise behaviour. The whine is still there but peak volume reduced. It however more consistant, so the whine is there when it's cold or when it's been driving for 6 hour straight, the difference in volume when hot is more but only marginal. With 80w140 it is not as loud when cold but gets as loud when hot, probably louder. With the old semi synth 75w90 Penrite it got louder when hot.

This tells me that properties of the new oil are pretty consistent across temperate grades, where as the previous fluids, especially the 80-140w mineral isn't. So vs all previous fluids it seems like the oil is maybe moving better when cold but staying together better when hot. Based on at least the behaviour in my truck I'd recommend running this throughout the drive train.

The bonus is they deliver, and cheap, 20l for this fluid and 20l of their semi synth engine oil, delivered for about $220 AUD ($140USD) I probably wasted more than that stuffing around with other fluids haha.
Probably not much help to those out of Australia though,
 
Thank you for sharing the trouble and your trouble-shooting. Very useful.

You dog is awesome. Good luck
 
Status
Not open for further replies.
Back
Top