Cracked Differential-Is He Lying?

illtrythis · October 10, 2006

I know just enought about trucks to be dangerous and can't tell if my son is telling the truth or not. I bought him a 1999 2dr Tahoe 4x4, in pristine condition, which we have already driven for a year with usual wear and tear repairs only. The other night, I had to have the truck towed to the shop b/c the rear wheels were locked up. The mechanic opened up the transfer case and it's completely cracked down the middle, with pieces of gears the size of my thumb laying in the transfer case. It still had quite a bit of differential fluid left in it.

Was he rock climbing or trying to fly it perhaps? His and all his friends' official story is that he noticed some differential fluid leaking from it, and was going to change it, and that it probably got hot and that's what cracked the differential.

Can a differential break from street driving, hitting a bump or a wallow? Or does this indicate a serious shock load? I don't want to convict him just yet, but I know him and all of his friends really push their trucks to the limit. I've explained to him this is not a serious off-road vehicle, and with 95,000 miles on it, he needed to baby it in the first place.

HELP!!!!

Nice rig · October 11, 2006

Do you mean rear end or the transfer case that is bolted to the rear of the tranny?? If the rear wheels locked up and the rear end grenaded I can believe it, especially if it was leaking fluid for any amount of time and wasn't taken care of. I have seen pictures of a rear differential explode...expensive, but cool looking.

ZZ327 · October 11, 2006

ive see one get annihilated on a rock. cracked open with fluid leaking out. never on a stock vehicle though. I have heard of it on drag cars though!

mmmikkke · October 11, 2006

The differential is at the center of the rear axle, between the 2 wheels. The transfer case is up near the front of the vehicle, near the transmission. Both have gears in them, and both can be broken. The same causes can break gears in either unit.

If you drove the vehicle for a year before giving it to your son, you probably would have noticed if there was anything funky going on with either the transfer case or the rear differential. So I'll assume both were working fine, and not making any weird noises, for the previous year of family driving.

But now suddenly either the differential or the transfer case has had a catastrophic failure.

I'd say there's a good chance that abuse caused the problem. I'd examine the rear tires for linear scratches in the tread indicating that some burning of rubber has been going on. If somebody did some serious wheel spinning at full throttle, the evidence should still be visible on the tread of one or both of the rear tires.

68vette · October 11, 2006

I know just enought about trucks to be dangerous and can't tell if my son is telling the truth or not. I bought him a 1999 2dr Tahoe 4x4, in pristine condition, which we have already driven for a year with usual wear and tear repairs only. The other night, I had to have the truck towed to the shop b/c the rear wheels were locked up. The mechanic opened up the transfer case and it's completely cracked down the middle, with pieces of gears the size of my thumb laying in the transfer case. It still had quite a bit of differential fluid left in it.

Was he rock climbing or trying to fly it perhaps? His and all his friends' official story is that he noticed some differential fluid leaking from it, and was going to change it, and that it probably got hot and that's what cracked the differential.

Can a differential break from street driving, hitting a bump or a wallow? Or does this indicate a serious shock load? I don't want to convict him just yet, but I know him and all of his friends really push their trucks to the limit. I've explained to him this is not a serious off-road vehicle, and with 95,000 miles on it, he needed to baby it in the first place.

HELP!!!!

<{POST_SNAPBACK}>

Well in the last couple yrs Ive replace the trans, transfer case and rear end in my Burban. My transfer case was CRACKED! I had a vibration that got worse over time, took it to a friends shop who looked at it and he said he cant find anything worng . . everything was nice and tight. TIGHT WAS AN UNDERSTATEMENT, THE UJOINTS WERE SEIZED! I only found this out after I had taken it to a trans shop a friend of a friend owns who rebuilt my transmission a yr earlier. Mince cracked under normal driving, the odd 4x4 on the street once and awhile but I never abused it or trying to take flight with it.

Chris

asilverblazer · October 11, 2006

If you can't trust your son with owning up to being responsible on this relatively minor issue, I wonder why you trust him out in a vehicle in the first place.

When I started driving I EXPECTED my parents to trust me, especially since they were letting me out on the road where I could possibly endanger the lives of others. Because of that they always gave me the benefit of the doubt. I would suggest you do the same. You might get burned once in awhile but at least your son will admire you for trusting him.

I know not what you asked...

It's a high mileage 4x4 things break, and sometimes weird things happen, normal or not.

doverarjim · October 11, 2006

This is not a transfer case story or to defend your son, now with that said let me tell you a little tale. In 1974 I worked for a 1967 Chevelle SS 396, when I got it and started putting it back together, carb, 4 speed and front bucket seats had been removed by some jerk and I paid $200.00 for it as it sat. The motor did not have any oil pressure so we got to checking and found that the oil pump did not work for some reason so we pulled the oil pan and replaced the pump to get the oil pan off we jacked up the motor on the balancer with out any problems. Start the car and it runs fine, after some playing around with it as my daily driver runs a 12.35 at 100 MPH at the drag strip. Now I drove this car like I stole it all the time, I had no fear of any car on the road. One day in 1976 I had been driving it for a little over 2 years, I pulled out of work and did not get on it or anything and it started knocking like crazy. I drove it about 4 miles to a buddys house and we started pulling it apart, thought that I had thrown a rod but every one of them were ok so I went to pull the crank out of the block and when I pulled on the snout and rear flange I had a crank shaft throw and the snout in one hand and the rest of the crank was still in the block. I made you read this to say that just because it breaks today does not mean it got hurt today!!! Cut your son some slack and see what happens.

different_seasons · October 12, 2006

If you can't trust your son with owning up to being responsible on this relatively minor issue, I wonder why you trust him out in a vehicle in the first place.

When I started driving I EXPECTED my parents to trust me, especially since they were letting me out on the road where I could possibly endanger the lives of others. Because of that they always gave me the benefit of the doubt. I would suggest you do the same. You might get burned once in awhile but at least your son will admire you for trusting him.

<{POST_SNAPBACK}>

He said what I was thinking......

yukon4wd · October 22, 2006

... I don't want to convict him just yet, but I know him and all of his friends really push their trucks to the limit. I've explained to him this is not a serious off-road vehicle, and with 95,000 miles on it, he needed to baby it in the first place.
...

Things break. I remember once many many years back I was driving mums car, reversed slowly out my mates drive late one night, Put it in first, put it in first, let the clutch out, and bang. Rear axle snapped, and dumped a chunck of metal in the diff. I hit the gas, and a few seconds later there was a grinding noise. Once I opened the diff, it was full of scrap metal.

Basically it was just metal fatigue, but the damage was incredible. d**n hard to convince mum that I was driving normal of course.

Any way 100k miles, you gotta expect something to break. I am in Europe now with my Yukon, and its amazing. You hear all the stories of 250k miles on these European cars, which is just BS. They are exstatic if they see 100k. Yeah Chevies are built tough, but every now and then something breaks. Its not worth the risk of loosing the trust of your kid, when there is a 90% chance that he's telling the truth.

drumset5994 · October 25, 2006

I guess this is just a case of "do you believe your son or not"

Even if he is lying, he'll realize in his head "woah...all those burnouts and off roading really destroyed a vehicle my dad took care of"

My brother (not comparing) has a tendency to throw some tall tales out there. He complained about his S10 having a "weak rear end" and that "all the S10's rear's go out because they so s**tty".

He doesnt realize he was at my place of employment, spinning dounts in the middle of winter, hitting drive pavement and smoking as i watched him on the cameras inside.

I dont think he still knows to this day.