Originally Posted by: HK1837 TH400 was put in as the 308 became too powerful in HJ, simple as that. GM had specific torque figures vs vehicle weight at which they changed to a different transmission and rear axle. The reason HQ got a TH400 not a TH350 is the 4BBL L48 had more torque than the maximum torque allowed in that size vehicle. I have never had a hydraulic controlled auto drive better than a TH400, they are bulletproof and shift fine when they are new. If you wanted to change gears manually you bought a manual.
The HJ 308 ? HJ ute and P van only got a single exhaust and was gutless as.
The 308 LH Torana from 10/74 to 6/76 got a tri matic and banjo diff.
A HX-Z, LX, VB, WB, VC, VH, VK, VL 5.0L V8 with a Automatic could not pull a sailor off ya sister. even a VK EFI 3.3L can hose them all off.
The T400-T350 was dopey power robing auto that kicked down was slow to respond right from new, it was no performance auto.
I seen a test of a 1975-6 ? Pontiac 455 T400 auto that came to Australia and they commented on the performance of the auto in how this T400 was responding so much better than all the other T400 in other cars they had ever driven, so it was modified to complement a enthusiast driver behind the wheel, now it was not C4 but this one was better than our HJ boring T400.
Most people are that stupid that they think that a auto is only about taking off and holding it flat through 1st to 2ed and top, well the T400 does that just fine. but the thing is if you can truly drive a car you use the T Bar for good reason, as such you will pull it back into 2ed on some fast corners so you are set to respond much better to throttle commands, this keeps one it total control and also you are not having to second guess if it's going to drop back into 2ed or not and not to mention the slow to responding kick down drive you up the wall and on sharper corners you want to drop it back to 1st at 60KM/H or so to hang the arse out even coming out of the corner or to control the rear coming into a corner and then nailing it on just the right spot setting the tail up for the job on hand with such precision. it's all about being able to control the car to your demands.
As I pointed out Ford has the same shocking dull responding autos as well like the FMX and C6, when the XT GT came out the Auto was magic thing to use because it was a C4 automatic and when the XW GT came out they were making claims that this auto was going to be modified to respond like the C4, but it did not live up to that greatness at all, as it was only a FMX auto and test drivers were bitterly disappointed in it.
If you have ever driven a XW-Y-A 4sp manual you would know that they were a pain to change gears with when changing fast hooking in all day long, it felt as tho I had been punching people all day long with that hand. and when I got a XB T Bar ute with a C4 auto that was behind a 351 with only a 2 barrel carby mind you from factory, so with the torque of the 351 you did not need a 4sp at all, I was like f that 4sp junk this is the only way to travel, it did everything you wanted it to do, I could not complain at all, apart from them XA-B-C being rust buckets.