Big plans for the heavy chevy

[Gordinho80]

Couple of hundred miles on my gears so far and the BRAKE and ABS lights keep cycling on/off like others on here. I'd love to hear how to resolve this as well!

[DirtyBacon04]

No luck on getting it fixed... I did notice that i can wheel for hours without the lights coming on, though. So i still get ABS on the trails. Just gotta turn the truck off and back on at the beginning of the trail. As long as your speeds dont exceed ~45-50 it'll stay off.

One interesting development in my 4.10 swap... Not sure how to describe it. 2wd, would drive normally. switch into 4hi it seemed to encounter some resistance. For example. in 4 hi, when i lift my foot off brake in D, the truck would not move, but in 2 hi, it would. I'd get positive engagement of the TC. Also driving in the 4hi, the truck steered oddly. would pull to the right primarily. Come to a stop and switch into 2wd, i would be greeted with a lound CLUNK and the front right corner would jump up to normal ride height. Unable to spot any discrepencies in the drive train: checked both driveshafts, u joints, checked proper installation of CVs and disco. I continued in 4 hi and the symptoms became less and less to the point where i dont get that CLUNK when i switch into 2 hi anymore. Thinking it must've been somethign with the new front diff not being used in so long, i had to wake it up.

[Gordinho80]

I haven't really ran in 4 with my setup yet. I'm still a little uneasy about everything considering the truck is currently the only vehicle my wife and I have (We're looking at leasing a new car for her soon).

I did put it in 4HI for a second last night after driving 30 minutes. I was at a light, 1 block away from in-law's house. It seemed sluggish and it had some extra vibration. I didn't even hit 25MPH before turning it off and pulling into driveway.

I'll be changing in the rear diff oil in a couple hundreds miles. Once I make sure that all is well and that we have a new car for wife, I'll test 4 a little more.

One thing I'm just noticing now... RockAuto lists my ring and pinion as 4.11 ratio, not 4.10... this adds to my uneasy feeling.

[DirtyBacon04]

Ruh roh.
I had that feeling initally when i was feeling the resistance. But if i had different ratios between front and rear, wouldnt it explode rather quickly? With a lot of noises/vibrations just prior?

[Gordinho80]

There in lies my concern. I don't know if the ration truly is 4.11 or what. Its strange....

[Regulator1175]

For what its worth, I have approximately 500 miles on my 4.10 swap including 2 days of heavy off road use in 4lo, and have no issues as described above.

[Gordinho80]

I'm thinking I should have tried to find another EXT axle with 4.10s already in instead of putting in new ring and pinion. Why would RockAuto sell 4.11s for the TB though???

[ErikSS]

I'm thinking I should have tried to find another EXT axle with 4.10s already in instead of putting in new ring and pinion. Why would RockAuto sell 4.11s for the TB though???

All TBSS's and some 5.3's come with 4.11's. There could be others.

[Shdwdrgn]

All TBSS's and some 5.3's come with 4.11's. There could be others.

Wait... what? They don't come with 4.10's? Now I'm getting scared too. The front diff I installed came from an '07 SS, but my rear axle came from an '05 EXT. Should I be worried? Everything I read said the diff from an SS would be correct for my swap.

[dvanbramer88]

I see a solution here.. Mario and Jeff trade front diffs. Mario will have 4.11s and Jeff will have 4.10s.

[mikekey]

I'm thinking I should have tried to find another EXT axle with 4.10s already in instead of putting in new ring and pinion. Why would RockAuto sell 4.11s for the TB though???

All TBSS's and some 5.3's come with 4.11's. There could be others.

Where did you get that info?

4.10's Erik.

Btw, some 4.6l came with 4.10s as well.

[ErikSS]

I'm thinking I should have tried to find another EXT axle with 4.10s already in instead of putting in new ring and pinion. Why would RockAuto sell 4.11s for the TB though???

All TBSS's and some 5.3's come with 4.11's. There could be others.

Where did you get that info?

4.10's Erik.

Btw, some 4.6l came with 4.10s as well.

First, there are no 4.6l engines.
Second, I've learned a thing or two on here. haha I think it was Barton who told me about the 4.11's in the V8.
What exactly is the difference between 4.10 and 4.11? I've always used the terms interchangeably.

[mikekey]

First, there are no 4.6l engines.
Second, I've learned a thing or two on here. haha I think it was Barton who told me about the 4.11's in the V8.
What exactly is the difference between 4.10 and 4.11? I've always used the terms interchangeably.

I was on my iphone when I typo'd that. And actually there was a 4.6L in my Mustang, I meant the 4.2L

I've heard them used interchangeably too on various car sites. I was under the impression 4.11's where in Ford rear-ends and 4.10 in GM rearends. When I had my Mustang GT, I swapped out to 4.11's. The front diff I just sold was 4.10 and all the GM rear and front diffs I've seen listed on carpart have been 4.10's. You can upgrade to 4.56 at most with the stock front 7.2 or is (7.5) frack, I'm slightly dyslexia and mix my numbers up a bit. But yeah, around here somewhere you can only upgrade the front to 4.56 before you have to replace the unit.

Anyways, it's just another option 3.42's standard, 3.73 tow package (I have this) 4.10 tow package. SS had it by default (performance).

Funny truth, Corvette's often have 3.23's in them to get good gas milage.

[navigator]

this is hearsay but I seem to recall 4.10 and 4.11 being the same ratio, it was dependent on how you did the calculation or something but effectively it was the same gearing.

It might have been bartonmd that explained it. I'll have to search.

[ErikSS]

[mikekey]

Yeah I think so, 4.10:1 ratio likely has 41 teeth on the ring gear and 10 teeth on the pinion, whereas the 4.11:1 ratio likely has 37 teeth on the ring gear and 9 teeth on the pinion

[Cable810]

Extreme 4x4 said that there would be no harm done with a 4.10 up front and 4.11 in the rear and vice versa, its only off by .01 which won't hurt anything. Refer to Blazer SAS Part 1 http://www.powerblocktv.com/episodes/XT ... r-part-one

[djthumper]

It appears the 2004 are not meant to have their gears changed... Just a trend I have noticed.

[HARDTRAILZ]

Extreme 4x4 said that there would be no harm done with a 4.10 up front and 4.11 in the rear and vice versa, its only off by .01 which won't hurt anything. Refer to Blazer SAS Part 1 http://www.powerblocktv.com/episodes/XT ... r-part-one

Extreme 4x4...haha, having met Ian...not the best resource to get info, but pretty cool guy.

I know loads of people that swap in axles that run 4.10/4.11 or similar differences in ratios without issues.


No GMT 360/370 had 4.11 factory. None had a 4.6 factory.

[DirtyBacon04]

Ok so here's my fear...
The salvage yard mixed up the gear ratios for one of the diffs I got. the question i have now is, IF i were running differnent ratios, how quickly would the TC grenade? Would it be an instant effect or a drawn out process?

Here's whats happening. Tested in parking lot. Rollin on asphalt at 15 mph, switch to 4hi, i hear the TC motor, a seperate dull whine and i can feel and hear all four tires slowing/braking. Occasionally the front right tire will "skip" slightly. w/o any throttle, the truck will come to a complete top. There is NO visible abnormalities to the drivetrain, and I drove in 4hi for about half an hour on a trail the other night, so i figure if i had different ratios it would've exploded by now.