Turbo Surf Diff Woes!

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

BoostingLux

BoostingLux

10 Year
Joined
Mar 8, 2011
Threads
7
Messages
85
Location
Auckland, NZ
:doh::frown: after a weekends thrashing ive grenaded another front diff.... (number 4) the vehicle in question is a 92 surf with the IFS. And before the sugestions come.. i cant afford a locker at the moment, and i cant afford a SAS conversion. And yes i should just go easy on the loud pedal but i cant help myself!

My main question is would it be ok to weld up my front diff? i figure itd would create some funky steering issues but as my truck is selectable 4wd it souldnt be a problem on road? also would my auto hubs and driveshaft still work correctly?

even though im getting good at changing diffs (3 hours) im sick to death of doing it. is welding it up a viable option? if anyone sees any other problems ive overlooked or has any suggestions im all ears!

oh n heres my last diff! :wrench:
27082011(005).webp
27082011(006).webp
27082011.webp
 
If you weld the ring gear, the diff won't spin. You can weld those four smaller side gears in the center, but your pinion and ring gear happen to be the one that transfer power from drivehsaft to wheels.
 
May have misunderstood your question.

Welding the front diff to gain traction is what your asking? Then, it will cause ALOT of stress on your CV axles, general drivetrain bind, and may make it easier to shear the ring like you have.

I would say its a viable option, but may cause more harm in the long run.

Also, make sure to weld it correctly! I've heard horror storys of welds breaking loose from improper cleaning and locking the diff up solid.
 
any idea why they're shearing?

getting stuck and smashing the gas?

if thats the case and thats the way you drive, welding the spiders Im sure you're going to break everything else...

if you end up welding Id definetly look into manual locking hubs.
 
Is this the same type of damage you've done to the other 3 diffs?

A locker or welded diff won't reduce the stress on the gears, that's for sure. Would probably exacerbate the problem in fact.

Are you jumping your truck or something? Is that how this is happening? I wouldn't say I thrash my truck, but I have certainly put a lot of power into it trying to hop out of creek beds and stuff--yet I'm still on differential #1, and 300,000 miles.

One way or the other, you want to put on the manual lockout hubs. Not only can you disconnect all those bits if you break it, but not having them spinning reduces the wear on the CV boots by an order of magnitude. I had one fail, fixed it and put the lockout on at the same time. My other CV boot has been "about to fail" for about the past 6 years. Easy way to make CV boot replacement a thing of the past, IMHO.

Dan
 
What are you doing with that rig? Ambulance, cop or road racer? That is not typical damage. In that one section of your ring gear that's clearly visible, 10 damaged teeth in a row and I can see other damaged teeth, also. I can't imagine what the pinion gear looks like. :eek: Only way you're going to fix your "diff woes" is to change your driving style. Unless you can afford your own pit crew to follow you around, parts trailer in tow.
Edit: Are you sure your auto hubs are not staying engaged? If they're malfunctioning, you could be driving around in 4WD full time. This would put more stress on your diffs, axles, drive shafts and T/C, but not to the extent showed in the pics. At least not immediately.
 
Last edited:
as i understand it, the reason for my diffs blowing so much is A: yes my driving is a tad aggresive. but mainly B: as it is an open diff, if im getting wheelspin on one wheel say coming up a ditch and one front wheel drops and starts spinning, then they both come out and get grip suddenly the shock of both wheels binding up is too much for the diff to handle so the gears are snapping.

I go offroading with a group of buddys who all exept one own surfs, and theyve all blown diffs, one with a V6 has blown 5 over 3 years. so clearly it is a weak point with these IFS surfs. the one that doesnt owns a suzuki vitara and is on his 3rd SAS diff!

Idealy id convert to SAS with an LSD or a locker. but im struggling to understand how a locker is any different to a fully locked diff, eg both wheels fixed spinning at the same time. i understand that in a full time 4wd eg a landcruiser this would make a mess of the whole system, but as it is selectable, and i only use 4wd offroad i dont see how its would be too much of a problem?
 
Last edited:
The US spec IFS rigs use a smaller diff (7.5") on the front, also the housing is relatively weak, so tends to allow flex, the ring to move away from the pinion under load. A big part of gear strength is in the setup, by increasing carrier bearing preload, you may gain some strength? But they are relatively weak units and likely not worth it?

Once you start beating them hard enough to pop them often, the best plan is to swap to something stronger. Even if you were to increase the diff strength, the axles, CV's, etc, will be next to go. A locker or welding will only make it worse, increase the stress on everything.
 
thanks, i may just leave it then untill i can afford a locker or just change to SAS or get a new truck all together
 
i believe boostingLux's concern is preventing excessive wheelspin to the wheel without traction (i.e. the one in the air, as he put it) transferring to instant diff gear contact when that wheel in the air lands back down or grabs onto something.

perhaps welding it to perma lock will help from falling into those open diff/traction loss scenarios. And prevent this damage from happening again.

obviously, wheeling smarter by not flooring it when one tire is spinning is key but he's asking for an alternative to this route. these trucks are tough but they arent immune to abuse. try driving the same way in 4high. fewer roations might help reduce the smack to the gears when you drop down and gain traction.

i personally hate tackling a climb with careless excessive power, not because things break but because its cheap. technically any car with decent clearance, power, and momentum, can clear a climb. doing it carefully and slowly, picking the right line, readjusting off a bad one, having a proper spotter, etc, excite me more. the whole strategic aspect, you know? but to each his own.

a locked diff will help keep traction but if youre giving it too much gas you'll just put wear on the diff in a slightly different way and break it again.

you do seem to have developed an expensive habit though. haha, good luck either way.
 
Traction will certaily be better with a welded front diff, but with the kind of driving you are doing you will bust cv axles every time you go out with the welded front diff. Learn some driving finesse and quit using the stupid pedal, then and only then will the welded front be an asset instead of a liability. The welded front will RIP the wheel out of your hands and break your thumb if you don't keep your thumbs the heck out of the steering wheel. I know this from personal experience.
 
yeah i know this, no thumbs lol. anyway i am using the gas to try an get out, im doing some savage tracks and as axed said. with the open front one wheel drops into a hole and i lose all drive as the wheel just spins. then as the rear is pushing the front forward and out its getting traction on the spinning wheel and boom. anyway i think ive got the info i needed, now people are just calling me a retard for how i drive! thanks!
 
BoostingLux said:
.......... now people are just calling me a retard for how i drive! thanks!
Click to expand...

No-body's calling you that. There's just a concept you need to grasp: Your radiator fan will not propel you very far. Meaning, revving the motor when your wheels have no traction can cause a boatload of surprises.
 
ok.... so today im just towing a trailer of firewood through a paddock in low4, get to a small creek, and have to gas a bit to climb out of the other side on wet grass. and boom. knocka knocka knocka. another IFS diff. its starting to get beyond a joke and im starting to hate my truck. for the first coupla diffs i was driving like a rapist. for this last one ive driven like a nana. no wheelspin, no jumps nothing. and its still grenading. i need a solution to this problem! can anyone help?
 
I would start checking the housing for warping at this point.
Maybe after all the destruction in the past, it's caused some structural issues.
 
Combat Chuck said:
I would start checking the housing for warping at this point.
Maybe after all the destruction in the past, it's caused some structural issues.
Click to expand...

Good point, It may be time to get another third member to start with. Might be good to have a built extra in the garage ready to put in when the next one goes.

I may have missed something in the above posts but proper gearing and a locker or spool may help you stay out of the gas. Typically if you have more traction you will be less likely to need excessive power/gas. If you have a spool or locker it you may have enough traction to get through the ditches with hammering it.

You could give it a try, the worst that could happen is you break and need to replace something else instead. Maybe it will be a cheaper part or one easier to fix or get to.

If that does not work then you need to do a SAS or step up to a 60 or 70 series Landcruiser.

How big are your tires and what gears do you have in your thirds?
 
yeah i was thinking that about the locker, but everyone just thinks ill break everything else. im going to buy another spare diff once this ones in and weld it up and give it a go. cant be any worse than these IFS ones at the moment. going to fit manual hubs too before the locker so if it does go bang again i can just unlock the hubs, my auto hubs play up when the diff blows for some reason. Oh and i am replacing the housing each time. total replacement, not just the diff head. im running 33s on the standard 4.56 ratio diffs
 
diff number 4 RIP
22022012(005).webp
22022012(004).webp
 
You must log in or register to reply here.

Share this page

Back
Top Bottom