Well, I've only heard of ONE 65 diff in a 60 as well. But I've heard of several HD diffs being put into 60'*.

So I suppose we're at an impasse here? We can go at this all day long, but I personally see no benefit to a major conversion when a HD unit can be built for less $ off the shelf.

There are 6 ways to skin a cat.

Why does it matter if the 65-HD diff is in the 60? The 65-HD diff is much more widely used then the $200 diff you have.
I personally so no reason to take a risk on a 4t60-hd diff.

I personally don't see any risk in USING an HD built diff in a 4T60. The guy that built my trans is a legend in the mid-valley here. Has been forever. Got a street rod that needs a good trans? You go where I went.

I don't see any reason or advantage to convert to a 4T65 diff whatsoever, considering the extra cost involved. I got a custom HD diff built for little more than a replacement OEM diff. I doubt seriously that I'll have problems with it since they are so confident in the build they've warranteed it for unlimited 2-wheel burnouts and speeds up to 135mph for tuning in preparation for the Salt Flats.

Mine sounds a little more 'safe' than a hybrid transplant.

Glad it sounds safer to you since your the one with it.
I'm not going to go that route since it dosent sound safer to me.

BTW, I meant electric water pump

I know of way more than one GP GT with the stock regular 65 trans (non-hd) that run in the 11'* and 12'* with no problems. The diff is plenty strong enough.


I can't very well understand why both tires wouldn't be spinning the same speed, if you apply enough initial torque it should just spin the whole diff case and the spider gears themselves shouldn't be spinning, I know its possible to spin them at different speeds but I don't see how its likely if you apply enough initial torque to it. With a stock differential our GTP actually has significantly LESS torque steer than it had when it had LSD'*. With the LSD'* it had it would pull one way and as your fighting the torque steer one way it would just suddenly pull the other way and so you'd have to start fighting it the other way and the car would quite often find itself in a different lane then was intended, with the stock diff it usually doesn't have torque steer, but when it does it just pulls one way and you can fight it to keep it straight and it doesn't pull back. With the stock diff in the GTP we've never had a one wheel burnout at the strip, which wasn't even close to the case with the LSD'*.

I agree 100% with this. The stock diff is an open diff, so it obviously is possible to do one wheels with it, and the stock diff isn't the strongest, although it has proven to be strong enough to pull 2 GP'* into the 9'*. The Intense Gen II has the issues that all of us know about so its kind of unreliable I guess. The c-ya is like a Gen I Intense, which now that Intense doesn't sell them, they'll even tell you themselves they were junk, and if they don't, I sure will. The quaife is very nice, but I've heard of some failures with it, and at like $1100 IIRC, the price is a bit steep.

Shawn

95, while I applaud you for 'going the different route' with your car, I must say I disagree with you wholeheartedly. I have a part in my transmission built by a man who is far more of an expert in it than you or I, and it was specifically built for my trans, not some other trans. Until you see it blow out my diff cover, you have no call saying it'* any worse than the 65 diff in my trans. You basically have NFC.

How the HELL can a hybrid transplant part be better than something you don't know anything about? If you think I'm bs'ing you about the builder on my trans, that'* your problem. I think most of the people here will see the logic in a HD built 4T60E diff in a 4T60. The OEM diff has one problem. Broken pins. If it'* beefed up to prevent that, why the hell would you want to do a transplant of a part not designed for the trans?



You go with the 65 diff, and we'll compare notes once you get your car running right and get some miles on it. That gives you the advantage considering the torque difference.

In the meantime, I'd suggest the BEST route for a 4T60 rebuild is a part designed and built for it.

Unless of course you're trying to run 9'*, but somehow I don't think you and I fit in that category.

Bill, I don't think you are bsing me about your builder. But I don't know him nor have I heard anything bout him from anyone else with a 4t60. So knowing only 1 person that has a 'custom diff' from this guy with low miles dosen't make it the best option IMO.
As for having "no call saying it'* any worse than the 65 diff in my trans", agian all I'm trying to say is your 1 person with this 'custom' 4t60 diff. And as for having NFC... Okay...Sure.
The point I'm trying to make is the 4T65-HD diff has been put into the 12'* n/a in a 4t60. The 4t65-HD diff has also launched cars much faster than that. Your diff is built by a local legend that I've never heard about. That is a risk to me. Maybe not to you since your familiar with the shop etc. but I'm not.
Have your opinion, I don't care. I'm not trying to change it.
In your opinion your 4t60 diff is better. Great! It works out too since you have one.
IMO I don't sooo I'm not going to get one. I'm going to get a 4t65-HD diff.

My point is the HD parts in my diff are OFF THE SHELF for the 4T60. There'* nothing new or magical here. Why go to the expense of a conversion to a 65hd Diff when there'* stuff available already?

The only reason the 65HD diffs don't have the durability issues the 60'* have is because they don't deliver their power down low like the Series 1 does. Not because it'* a stronger or better diff.

Is it stronger than the 65 non-HD diff? Almost certainly. Is it an advantage to you?

Hell no. If I can't break my diff, you can't break my diff built with off-the shelf parts either. This stuff has been around since the 4T60 was invented.

My biggest pet peeve here is that people spend unnecessary money for stuff they don't need. Your L36 isn't going to break a 4T60HD diff. It'* just not going to happen, even if you Turbo that car. It doesn't deliver the low-down torque the S1 L67 is famous for. That 4T65E diff is ridiculous money spent for your car.

I understand you're fascinated with it, but it'* much like the Walbro fuel pump in my car. It sounds cool, but the bottom line is that it was cheaper than OEM. In your case, it sounds cool, but I really don't think you need the trouble or expense. If you want to, that'* great, but it shouldn't be bragged as the way to go, because very few cars out there would benefit from the conversion you're talking about.

I don't like seeing people dump money into a pit.

Gents, the one thing I've taken out of your spirited debate is this:

If I can get a heavy duty differential machined specifically for the 60, that is probably the best route. However, in the situation that isn't possible, hybriding the 65 differential is a viable solution.

Both of you are making valid points for the reasoning behind your opinions, but I think the point'* been made. Thank you, both of you for all of your input.