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A518 auto shift questions etc

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I've noticed that at times the A518 doesn't want to shift up when I think it should, when its cold. If I get in after its been sitting for a day or two... and take off... it seems to "hang" in 1st a little too long for my liking. The RPM's will go up to where I think it should shift then I'll hold it there. A few seconds there it will finally shift. Once warmed up... it will shift normally.



Any adjustments for this or just the nature of the cold fluid and "unfilled" TC?



Also... I was playing around with removing the Valve Body and accidentally turned the line pressure screw CCW a turn or two thinking I could remove the VB easier by removing more parts. That was a mistake when I saw there was a spring behind the screw. I instantly realized it was an adjustment screw and not a bracket screw. So I turned it back 1 turn not realizing exactly how far I had gone. No more than two turns anyhow. (Dumb I know... but it was HOT in the garage, shop light was in my face, and I had never seen the inside of the 518 before).



Will one turn extra on the line pressure screw CCW hurt? DTT site says 1 turn CCW is 5psi more pressure. Is there a way to take it to baseline without gauges for pressure? IE: fully turn in then back out 7 full turns? Or am I way out in left field?



Eitherway... I'm pretty close to what it was anyhow.
 
Idle it for a couple minutes in neutral to get the fluid flowing and see if that helps. Probably just seals get a little stiff and needing to warm things up good to seal.



Don't worry too much about the line pressure adjustment. A couple will make no noticeable difference. If it does, then you have other possible issues that will show up eventually. It should not hurt a thing. :)
 
There's an old TSB 21-19-94 that addresses that issue. you have to change the 3 teflon sealing rings on the governor body with cast iron rings. the new PN# 4461011. you'll have to drop the O/D unit and disassemble it to get to the governor, it's at the bottom of the O/D unit. If i was gonna go through that, I'd just drop the trans out and reseal/overhaul the whole unit.



NO: 21-19-94

SUBJECT: Delayed Upshift - 4-Speed (Hydraulic Governor) Automatic Transmission

DATE: Sep. 30, 1994

NOTE: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 4-SPEED (HYDRAULIC GOVERNOR) AUTOMATIC TRANSMISSION (42RH/46RH).



SYMPTOM/CONDITION:

Delayed upshift for about 1/4 mile in cold weather (32 degrees F and below). This condition is most noticeable after the vehicle has been parked for 8 or more hours.



DIAGNOSIS:

Allow vehicle to set for at least 8 hours. With the 100 psi Test Gauge C-3292 connected to the governor pressure port, start the vehicle and put the transmission into Drive. Slowly increase vehicle speed. The governor pressure should increase in proportion to vehicle speed. Disconnect test gauge C-3292 and then drive vehicle for about 1/4 to 1/2 mile. If the vehicle does not upshift within this time period and/or the governor pressure does not match the vehicle speed, perform the following repair.



PARTS REQUIRED:



(3) 4461011

Seal Ring - Transmission Governor Drive (Cast Iron)



REPAIR PROCEDURE:

This bulletin involves replacing teflon governor drive seal rings with cast iron seal rings.



hope this helps,

Dave
 
Thought I knew which transmission I had but trans shops are either confused themselves or I am. Its a 1991. 5 lockup torque converter 4speed auto. I'm calling it the A518.



I've been told its a A618. And how does this correspond to the RH/RE46, 47? R is rear wheel drive... H is hydraulic and E is electronic? 4 is 4 speed? But which do I have?



Is the A518 a RE46 or so forth? How can I tell? (glove box sticker which I have not looked at, just now thought about that)?



FWIW... I ordered a Sonnax Manual Valve and a Regulator Valve. Both of which will do a few things for me. Mainly give me good flow in park, allow better flow at full power, eliminate the cooler line drainback valve (restrictive) and smooth the reverse engagement. Both are easy to install. I just gotta verify my line pressure in idle/drive even though they give base settings for the regulator valve/line pressure adjustment. Sonnax said if I follow their instructions I will be pretty much dead on.



I also have a feeling my bands are way out of spec. Gonna take care of that too.
 
Thought I knew which transmission I had but trans shops are either confused themselves or I am. Its a 1991. 5 lockup torque converter 4speed auto. I'm calling it the A518.



I've been told its a A618. And how does this correspond to the RH/RE46, 47? R is rear wheel drive... H is hydraulic and E is electronic? 4 is 4 speed? But which do I have?



Is the A518 a RE46 or so forth? How can I tell? (glove box sticker which I have not looked at, just now thought about that)?



FWIW... I ordered a Sonnax Manual Valve and a Regulator Valve. Both of which will do a few things for me. Mainly give me good flow in park, allow better flow at full power, eliminate the cooler line drainback valve (restrictive) and smooth the reverse engagement. Both are easy to install. I just gotta verify my line pressure in idle/drive even though they give base settings for the regulator valve/line pressure adjustment. Sonnax said if I follow their instructions I will be pretty much dead on.



I also have a feeling my bands are way out of spec. Gonna take care of that too.





47RH probably and it ain't stock. :) If it is an RE you will have a 10 wire round plug for the controller instead of the flat 3 wire plug. So what is controlling your lockup?



I use the Sonnax valves in both of mine. They work well. While your at it ya might as well toss a shift kit in the VB since you will have it partially apart anyway.



Makes a big difference in the lockup apply and holding power.
 
I have no reason to believe its not stock. I was just operating under the assumption that when it was new... Dodge installed what I think is the A518. Then again I'm no expert. Was a 91. 5 even available with lockup?



IIRC... there is a connector on the shift linkage side thats yellow with two orings on it. Just bolts to the VB with one screw and has a couple of pins (two or three, I cant recall as it seems I'm never around my truck when I think of this stuff). That deal has a black and red wire that runs under the VB and goes to what looks like a solonoid on the passenger side. I was assuming that was my lockup solonoid setup. There is definataly no 10 pin connector there anywhere.



I unplugged the neutral safety, the "lockup" connector, the speed sensor on the tail, and one connector on the cooler line if I remember. I removed the entire harness back up to the engine bay so I can clean the trans good and just have the wires out of my way. The harness all looks original with the cloth tape and fastened along the way like appearing original. Its all tied into my engine bay harness and has no signs of tampering or adding anything different than what Dodge installed.



One transmission shop (wihtout seeing the truck) told me it was an A618 "because thats what all the diesels have". But they have never seen my truck. Others didn't even ask really. Don't know if A618's were for the 2nd gen trucks. As far as I know... the drivetrain is all original equipment. When I look for parts online... everyone references them as 46's and 47's as if the models interchange with A518's and 16's.



Guess a google search is needed.



Which valve body shift kit is decent since I've already got the manual valve and regulator valve from Sonnex?
 
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One transmission shop (wihtout seeing the truck) told me it was an A618 "because thats what all the diesels have".



LMAO!! Did ya ask them if they could tell the difference between a Hyundai and a Dodge truck? :-laf:-laf



Ok, if you have OD and the trans is the original it is an A518 (46RH). The A618 (47RH) did not go into the Dodge diesel trucks until MY94.



To check, on the driver side of trans above and behind the neutral safety switch you will find a plug that is vertical into the trans mission. You should have 2 wires in the plug.



I am partial to Transgo but Superior makes a good one also.
 
Thanks Cerberusium. Thats what I needed to know. 46RH is what I thought. And I do have the two wire vertical connector by the neutral switch. Thats what I was calling my lockup control to my solonoid on the Valve Body. I guess A518 and 46RH names are interchangeable.



Well... I think the trans shop in question meant "thats what all diesels have" refering to older Dodge diesels. But to him older meant older 2nd gens. Cause was suprised when I said mine was a 91 WITH a Cummins.
 
46RH is what I thought. And I do have the two wire vertical connector by the neutral switch. Thats what I was calling my lockup control to my solonoid on the Valve Body. I guess A518 and 46RH names are interchangeable.



A518 and A618 are the older designations. Parts number and item designations seem to be a revolvong door with auto companies.



The 2 wire connector is the OD control. The larger wire is 12V supply and live when the key is on. The smaller wire is the OD sense wire. When the PCM demands OD it grounds that wire to engage the OD solenoid. When the PCM freaks out it doesn't ground that wire and you get no OD.



Thats where you tap a mystery switch onto the wire and the other end to ground so you engage OD when you want. :D
 
OK. Learning alot here. Then I have no lockup it seems. :( Oh well... I still get better mileage than anything built within the last 10 years. :)



I ordered my Sonnex items from -Whatever it Takes Transmission- in Louisville KY. Mainly because I get next day deliveries using just UPS ground. In their explosion diagram of the A518... thats where I'm sure I saw the lockup stuff. I'll have to look again.



Speaking of OD and wires... my red wire running from the connector on the VB, then down across the bottom of the VB has cracking insulation. In some places the wires are showing well. Maybe do myself a favor and get a new one of those. Not sure if it matters though. Cause the terminal ends are bare connectors and are in a bath of ATF anyhow.
 
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