Monitoring transmission pressure

[66/440]

Is there a way to monitor transmission line pressure so that you can catch possible failures before they happen? What is the acceptable pressure range for a good front pump and how does that translate to accumulator pressures? Are they the same, is there a formula..80% of generated pump pressure etc.???
Can a gauge be plumbed to monitor these conditions and where would you pull the pressures from? Do you need two sources to get a differential pressure?
Enquiring Minds......

 

[commando1]

Are you racing?

 

[Big_John]

There are test ports in the trans case for pressure.

Your FSM will show location and nominal pressures.

 

[66/440]

So the easiest way is to monitor the servo pressure ports? Will this give enough advance warning of failure caused by a under performing front pump?
I am not racing but expect to be pulling fairly heavy loads over long distances and don't want to be surprised 3000 mi from home.

 

[Big_John]

IMHO, you would be better off prepping the trans right to begin with rather than trying to monitor pressure.

Aside from the rare catastrophic failure, the 727 gives plenty of warning that it's getting tired before it gives out.

If you really want to do this... Your FSM is going to answer your questions regarding pressure etc.

 

[66/440]

I have had lots of experience with torqueflites over the years and I know what to look for, BUT. There will be other folks who will be driving her as well who have little or no experience and I am anal enough to try and put together a drivers' do's,
don'ts and what to watch for these guys. It is difficult enough to relinquish the keys no matter how temporarily, especially after you sweat, bust knuckles and spend copious amounts of money. I just don't want some one who is uninformed/inexperienced to fry a drive train.

 

[68plymouth383]

It's real simple. Don't let them drive your car!!

 

[66/440]

It's real simple. Don't let them drive your car!!

Wish it was that easy. I am going to be able to take some of the expense of restoration/ renovation as a business expense if I use it as a marketing tool. That is going to require that it be used at events and trade shows as well as a kind of a road show for our business. That means some of the sales folks and marketing reps will be driving it to different events and handing it off as it works it's way across the country. Most of these guys are in their 30's and 40's which means that for the most part they have no practical experience with 1976 tethnology so I am trying to anticipate all the possible issues. To top it off they will sometimes be pulling a trailer which opens up endless possibilities that may have a negative result. BUT when the tour is done she will be retired to my collection. So hopefully a net positive gain.

 

[68plymouth383]

I hope it works out well for you.

Wish it was that easy. I am going to be able to take some of the expense of restoration/ renovation as a business expense if I use it as a marketing tool. That is going to require that it be used at events and trade shows as well as a kind of a road show for our business. That means some of the sales folks and marketing reps will be driving it to different events and handing it off as it works it's way across the country. Most of these guys are in their 30's and 40's which means that for the most part they have no practical experience with 1976 tethnology so I am trying to anticipate all the possible issues. To top it off they will sometimes be pulling a trailer which opens up endless possibilities that may have a negative result. BUT when the tour is done she will be retired to my collection. So hopefully a net positive gain.

 

[Big_John]

Well... Having had employees driving vehicles myself, all I can say is good luck to you.

IMHO, I don't think that monitoring line pressure is the way to go. It's a diagnostic tool best suited to back at the shop rather than on the road.

What is the transmission killer is heat. Along with good coolers, I suggest you do something to monitor the trans fluid temperature. If the trans slips the fluid gets hot. The fluid gets too hot and it cooks to a brown sludge that will destroy what is left.

So... a good temperature gauge and maybe even an idiot light might be the way to go. Think about it... The trans gets hot, the driver parks it until it cools off... and hopefully call you...

When it comes to employees and cars... Keep it simple. Really simple. I have stories.....

 

[commando1]

That's an excellent idea and I myself would do it that way.

 

[1978 NYB]

My 07 Titan 4x4 has a txsm temp gauge.....it's amazing to see how much higher and quickly the temp gauge rises when I'm towing something heavy (1978 C-Body).

 

[commando1]

My 07 Titan 4x4 has a txsm temp gauge.....it's amazing to see how much higher and quickly the temp gauge rises when I'm towing something heavy (1978 C-Body).

Was that standard instrumentation or did you add it?

 

[66/440]

My 07 Titan 4x4 has a txsm temp gauge.....it's amazing to see how much higher and quickly the temp gauge rises when I'm towing something heavy (1978 C-Body).

My Chevy truck has the same thing. There is about a 60 to 90 degree swing from normal when towing a boat or car depending on terrain.

 

[68Bigred]

I put a huges performance pan that hold an additional 2 qts of oil. Only issue is obiviously it hangs down further. Not an issue with my bigger wheels but with stock wheels it can hit speed bumps if they are large. The pan also has the fins in it which aid in cooling. Also My griffen radiator has a bigger core for the trans fluid. I would like to find a vintage camper and pull with my 300 so hopefully I wont have too much heat problems.