In the last 45 years or so I've only driven an auto a handful of times. I did have an auto for a couple of weeks while the great head replacement debacle of 2018 was going on though.Quote:
Originally Posted by rick130
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In the last 45 years or so I've only driven an auto a handful of times. I did have an auto for a couple of weeks while the great head replacement debacle of 2018 was going on though.Quote:
Originally Posted by rick130
I think I need to experiment a bit to work out TC lockup works for me while towing. I'll also have a bit of a play with sport mode too. From today's effort up to Walhalla and back I reckon I'll probably not use sport mode much.Quote:
Originally Posted by shack
From what I've read here and from what the auto specialist says TC lockup is key.
This car already has a brand new bigger auto oil cooler. It's also got a new ACE pump as well as steering and coolant pumps and has had the EGR removed as a bonus.
Next jobs are to get the second battery and brake controller out of the old D2 and into the new one. That should keep me amused for a few hours...
What do you mean by making sure it's locked? Locking it in 3rd you mean? And do you have a link to the ashcroft article?Quote:
Originally Posted by shack
I've hit the temp warning once or twice towing a van. Was able to stop pretty quickly however and all was OK, but it would be nice to avoid it in the future.
Depending on the load you are pulling, you may be able to tow in 4th locked, if it's a heavier load, then you may need to manually pull the selector back to 3rd and let it lock up, you really should try and avoid the temp alarm going off if at all possible.Quote:
Originally Posted by MrFollies
And no I can't find the article I was thinking of anymore, but there is a link on the 4hp22 FAQ page that shows just how deleterious increased temperature is for an Auto.
Keeping the converter locked is a well known method to lengthen box life and reduce and warping internal friction plates and such (all caused by temperature), as fluid temperature will lower with the converter locked
Cheers
James
Quote:
Originally Posted by shack
Here is the guts of it. More info on their website.
Thanks for the reply. Forgive my ignorance but it's still not clear to me. You talk about locking in 3rd or 4th and then 'keeping the converter locked'.Quote:
Originally Posted by shack
My understanding would be: Selecting a gear just disengages the upshifting... So if you select 3rd you are never going to get to 4th gear.
I assume the converter is locking (1:1) at a certain speed (or would it be RPM) and that's not something the driver has any control over. How do you know if it's locked?
So you are not talking about locking the selector, rather using the appropriate gear to encourage the converter to be at 1:1 and therefore not heat up the oil anymore?
Ok,Quote:
Originally Posted by MrFollies
If you select 3rd, the vehicle will use any gear up to and including 3rd, if the Auto is in good health and the load on the vehicle is not too great, then the torque converter will lock itself, you will often notice engine rpm dive somewhat without roadspeed changing, as the converter locks up.
The same applies too 4th, noting that when you do, the Auto will no longer lock in 3rd.
In a discovery 2 you can't get lock up in the other gears unless in low range.
To verify that you are locked, if you lift the throttle pedal, the revs will only drop slightly, maybe 50-100 rpm, if not locked then it will likely drop a few hundred rpm, depending on other conditions.
If the load on the vehicle is too great to reach lockup / stay locked in 4th, that's when you would pull the selector back to 3rd, and hopefully then it will lock.
Hope that clarifies it!
Cheers
James
In addition to the TC being at 1:1 modern transmissions have a clutch which locks the input to the TC and the output into the transmission.Quote:
My understanding would be: Selecting a gear just disengages the upshifting... So if you select 3rd you are never going to get to 4th gear.
I assume the converter is locking (1:1) at a certain speed (or would it be RPM) and that's not something the driver has any control over. How do you know if it's locked?
In a D2 in 3 selected the TC will lock at 70KMh and unlock once below 50KMH or if you use a lot of accelerator.
In 4th the TC will lock at 80Kmh and unlock at 70Kmh or if you use a lot of accelerator.
In addition if you flatten the accelerator the transmission will kick down to the lower gear.
The way to test is that you will notice on the tacho ,if you put your foot dawn at say 60KMH in 3 the revs will rise immediately until you get to 70kmh . then you will feel what feels like a gear change and if you ease off or accelerate the tacho will not move immediately but move proportionate to the speed of the car. The transmission may then change into unlock 4 until you get to 80KMh when it will lock in 4.
The lock up will not work until the temperature gauge is in the middle for a TD5 auto ie about 70C engine temperature.
Regards PhilipA
As usual Phillip has the numbers nailed, the TD5's seem to have troubles with their torque converters literally wearing out until it just wont lockup anymore,, not easy to pick, as the TD5's are designed to slip a lot more than the V8's...
Yep, the TC and clutch is smaller than the V8 one and is marginal according to Ashcrofts.Quote:
Originally Posted by Pedro_The_Swift
A modified V8 version is the go for the TD5, and it drops the stall speed too which works well with a remap.
The flexplate is prone to cracking too.