A518 adjustments

[bill-d-c]

I've got a 93 W250 with the A518 auto trans. I started out to just service the tranny, fluid, filter and gasket. The truck doesn't get driven much and the tranny seems to be working fine, truck has 114K miles on it. Now I'm wondering if I should try to make some adjustments since the pan is off. They would include the front kick down band adjustment, rear band adjustment, line pressure and shift points. I've never tried anything like this and am wondering, should I mess with it, or leave it alone. What advice can you guys give me.
Bill

[cmann250]

I followed this article: viewtopic.php?f=22&t=7759&p=58004#p58004

The bands have a set service interval, but I don't recall what it is. As far as bumping pressure, you'll get firmer shifts and less slipping (if there was any in the first place) in the clutch packs. Delaying the shift points really helped me because my old stock 727 seemed to want to get into 3rd gear ASAP.

One more note, I've never had luck with the rubber or cork pan gaskets that come with most filter kits. I have a Mopar reusable gasket and I bet I've had the pan off 6 or 8 times and still no leaks.

[bill-d-c]

Unless someone has different advice, this is what I think I'll do. Adjust both the front and rear bands, that sounds fairly straight forward. As far as line pressure, I'm thinking I can go CCW one turn and be OK. The gov. pressure screw (one with blue loc-tite) I can go CW one turn and be OK. I just don't want to screw up a trans that's working fine.

[simplysmn]

Hey Bill I have alway Heard if it's not Broken don't try to Fix it when it comes to a good working trans .

[oldestof11]

I put 3 full turns on my VB line pressure. That AND tractor hydraulic trans fluid.

The fluid has to be some of the biggest $/improvement for auto trans trucks with stock converters. I was averaging 17.2mpg with one tank at 18.1. My last 2 fill ups which included 6-8 Dragstrip passes on my last tank. They came out to be 18.3 and 18.7. The 18.3 was 4 qts low on trans fluid. If you don't catch my drift, 4qts low and I didn't notice it except before the fluid warmed.

[bill-d-c]

Hey Bill I have alway Heard if it's not Broken don't try to Fix it when it comes to a good working trans .

You are correct my friend, and I gave that option a lot of consideration. I did however do the service with adjustments and it seems to be working just fine. Did it help...if it did it was minimal. However, it didn't hurt...and that is what I was afraid was going to happen. This truck gets driven about 150-200 miles per year, so it should be good for a long, long time to come.
Bill

[monoblock]

Here is a link t a previous thread that discusses both Line and Throttle pressure adjustments.It seems we still need some data to be sure of what we are doing?
viewtopic.php?f=3&t=13888

[bill-d-c]

That's the article I used to make my adjustments. I wasn't very aggressive on turning up the line pressure but did some. Followed the band adjustment guidelines to the letter, seems to work fine. I appreciate all the info.
Bill