[LS2] Fitting Diff cooler on stranded ve zf diff

Shanessvredline

Donating Member
Sup people, so before I go stuffing s#@t up I thought I would consult with some people in the know, so here is the deal I want to fit a diff oil cooler on my ve ss so my new diff dosen't suffer the same fate as the last, just wondering if it would be plausible to run a line from the diff drainage bung to a stand alone pump then to the radiator inlet where the transmission fluid used to pass through then a return line back to the diff filler bung? Basically I'm trying not to have to install another cooler up front for fear of lack of air flow to the rad and my car is to low to put it anywhere else, my question is would plumbing it in to the old trans fluid location cool it enough to make a difference or should I front mount a fan and new cooler? Any help would be much appreciated ps currently running a 76c thermostat and have changed the fan cut in to 84c so it rarely hits 100c..anyone know what's optimum temp for the diff oil ? I'm guessing as cool as possible
 

07GTS

Well-Known Member
fluids should not run as cool as possable they all have a operating temp range usually about the 100c which is also best as any moisture/water can evaporate, for the diff if u have to just run a small radiator from the points u mentioned if it fits with exhaust there also, mount it maby behind the diff under the vehicle in some airflow and it should help, i wouldnt run anything to the front as the pump will have too much distance to pump oil just for the diff, u can look at the VF LSA GTS as it has a diff oil cooler standard for some ideas, u can also run a thicker diff oil so if the diff runs at a higher temp the oil will still keep its strength ive ran thicker in mine for years without issue
 

Shanessvredline

Donating Member
fluids should not run as cool as possable they all have a operating temp range usually about the 100c which is also best as any moisture/water can evaporate, for the diff if u have to just run a small radiator from the points u mentioned if it fits with exhaust there also, mount it maby behind the diff under the vehicle in some airflow and it should help, i wouldnt run anything to the front as the pump will have too much distance to pump oil just for the diff, u can look at the VF LSA GTS as it has a diff oil cooler standard for some ideas, u can also run a thicker diff oil so if the diff runs at a higher temp the oil will still keep its strength ive ran thicker in mine for years without issue
Thanks for that, I did actually look into the vf2 lsa cooler, was looking in to modifying that kit to suit but before I go cutting diff hats up I'd have a look around at what some other people have done....I honestly can't find a thread or a kit for sale anywhere
 

losh1971

Well-Known Member
Need to be careful modifying diff covers. If the original design is a smooth round dish it needs to stay that way. Some people fit custom hats but altering the shape of the dish changes the flow to the pinion and can make the oil slash around the back and not throw properly. On a proper round cover with nothing but the flat round surface the flow of oil gets thrown over the top and onto all the gears and bearings. I can dig out a vid of these blokes who test various covers and show you the problems caused by aftermarkets ones by using their own custom clear covers that match the shape of the aftermarket ones.
 

Shanessvredline

Donating Member
Thanks for that, I did actually look into the vf2 lsa cooler, was looking in to modifying that kit to suit but before I go cutting diff hats
Need to be careful modifying diff covers. If the original design is a smooth round dish it needs to stay that way. Some people fit custom hats but altering the shape of the dish changes the flow to the pinion and can make the oil slash around the back and not throw properly. On a proper round cover with nothing but the flat round surface the flow of oil gets thrown over the top and onto all the gears and bearings.
Yeah that's true....
Need to be careful modifying diff covers. If the original design is a smooth round dish it needs to stay that way. Some people fit custom hats but altering the shape of the dish changes the flow to the pinion and can make the oil slash around the back and not throw properly. On a proper round cover with nothing but the flat round surface the flow of oil gets thrown over the top and onto all the gears and bearings. I can dig out a vid of these blokes who test various covers and show you the problems caused by aftermarkets ones by using their own custom clear covers that match the shape of the aftermarket ones.
Yeah I totally agree and understand the importance of it, was going to copy this if possible, I understand it's a different diff but same principle
 

Attachments

immortality

Can't live without smoky bacon!
Staff member
Sounds like peeps been watching the Banks diff cover videos.
 

Shanessvredline

Donating Member
Sounds like peeps been watching the Banks diff cover videos.
I haven't actually watched any videos on it yet but I will, I'm a boilermaker/ diesal mechanic buy trade so this would be an easy job in theory...I'm just wondering if it would cool the oil appropriately for my application, but I work on locomotives not cars,
 
Last edited:

losh1971

Well-Known Member
I'm surprised that diff oil could get hot enough to cause problems on a DD. I've done plenty of towing caravans. Tow my trailer most weeks and that would be around a 1000kg when loaded. Different diff but I'd say the principal remains the same, heavy loads tend to be what puts strain on the diffs.
 

Shanessvredline

Donating Member
I'm surprised that diff oil could get hot enough to cause problems on a DD. I've done plenty of towing caravans. Tow my trailer most weeks and that would be around a 1000kg when loaded. Different diff but I'd say the principal remains the same, heavy loads tend to be what puts strain on the diffs.
True...in my case it's aggressive driving over long periods, hey I might be going completely over kill with the cooler idea as the last diff I fried was a standard 3.45 lsd and holden didn't really do the best job with the lsd center in them, my new diff has 3.45 hsv shot peened gears and a harrop trutrac but I'd prefer to be safe than sorry,
 

immortality

Can't live without smoky bacon!
Staff member
That'll be a much better diff for sure.

I can't see why as you suggested, use the drain and filler plugs with a small pump and little radiator mounted somewhere underneath won't work. I've not seen the diff cover in question but maybe it has enough meat in it to drill and tap separate fittings to suit. I'd stick with the stock cover after watching the Banks diff cover series.

Nice job BTW.
 

Shanessvredline

Donating Member
That'll be a much better diff for sure.

I can't see why as you suggested, use the drain and filler plugs with a small pump and little radiator mounted somewhere underneath won't work. I've not seen the diff cover in question but maybe it has enough meat in it to drill and tap separate fittings to suit. I'd stick with the stock cover after watching the Banks diff cover series.

Nice job BTW.
Yeah I think that will be the way I'll go, I'll give that vid a watch now for a bit more insight just for fun, thanx for your input man, appreciate it
 

07GTS

Well-Known Member
dont know about your exhaust but i have to remove mine just to undo those diff drain and fill points so not sure about fittings in to go to a pump as they will stick out least maby 2 inches further, and if yours does fit now any bigger exhaust in future then may no fit
 

losh1971

Well-Known Member
I have read that the stock diffs can have problems, possibly not necessarily from hard driving either. Strengthening it up as you have IMO will be a better upgrade than adding a cooler. As suggested run some 140 oil that should help too. I always run 140 in diffs after my diff builder recommended it.
 

Shanessvredline

Donating Member
dont know about your exhaust but i have to remove mine just to undo those diff drain and fill points so not sure about fittings in to go to a pump as they will stick out least maby 2 inches further, and if yours does fit now any bigger exhaust in future then may no fit
I'm running a 2.5" at the moment..it is still tight under there but hopefully I can figure something out.
 

Shanessvredline

Donating Member
I have read that the stock diffs can have problems, possibly not necessarily from hard driving either. Strengthening it up as you have IMO will be a better upgrade than adding a cooler. As suggested run some 140 oil that should help too. I always run 140 in diffs after my diff builder recommended it.
Might have to give it a go after the initial run in, cheers
 

shane_3800

Active Member
Just run 85w-140 LSD oil, this is what my diff guy told me to run. I'm a mechanic so I use a diff guy an engine guy and a trans guy and I trust them all.

The diff hat videos are from Gale Banks I watch alot of his videos mainly on tuning diesel's on the engine dyno. Steve Burle is also a very interesting engine dyno operator to watch he does all the magazine tests which is why he works with motortrend.
 

immortality

Can't live without smoky bacon!
Staff member
I'm not sure LSD oil is used with the truetrac centres as they don't use a friction/clutch setup so no need for a friction modifier.
 

Shanessvredline

Donating Member
Just run 85w-140 LSD oil, this is what my diff guy told me to run. I'm a mechanic so I use a diff guy an engine guy and a trans guy and I trust them all.

The diff hat videos are from Gale Banks I watch alot of his videos mainly on tuning diesel's on the engine dyno. Steve Burle is also a very interesting engine dyno operator to watch he does all the magazine tests which is why he works with motortrend.
Thanx dude, I'll check em out
 
Top