which replacement modulator?

[edpdx]

I went to replace the Tansmission modulator in the M1009. The guy at the parts counter said he had Fram parts only; but there was two type:
Fram - Transmission Modulator

Green Stripe or Blue Stripe?

Part Number: FM2321
Part Number: FM2322

Mine is a 1985. But looking at either part number's compatibility list should I be lokking at 1984 J-code K30 diesels or 1985 "C" code diesels?

 

[m816Buch]

NAPA catalog shows red stripe......#17499

 

[m816Buch]

new modulator is also adjustable

 

[raiburn]

Why did you replace it? I replaced mine chasing a gremlin.

 

[edpdx]

I am just getting a jump on general maintenance. There is some slipping when I start it up and put it in Drive. It comes along after 2-4 seconds. So I thought I would stat by replacing the rubber lines from modulator to the Injector pump. I replaced all the rubber in this circuit and Cleaned the fuel valve on the top (glass ball intact .

Noticed the power seemed a little better. I replaced the Modulator- O'reilly's only had the Fram FM2321 in so I chanced it. She said to bring it back if it is not the right one- the box is filthy; but if it is the wrong one... it is going back.

The shift point seemed high on 2nd and 3rd. So I rotated the VRV toward the firewall a touch- it did bring it down. It is now shifting around 19MPH into 2nd, Not certain on 3rd. Too many hills here. I'll run it over to the flats later.

Where are your shift points? Should I try to eliminate the slippage with the adjuster on the modulator?

I put about a pint of Lucas Trans Fix in to replace the fluid lost during the modulator switch-out. Seems to be less slippage; but it may be because things are warmed-up now. I'll wait till it cools and try it later. Any other ides on this Mod from fram- is there a better one is this the wrong one?

 

[edpdx]

Hey congratulations are in order I just made Corporal. Do I still have to work for a living?

 

[rnd-motorsports]

To check a modulater you pull off the vac. line if there is any trans fluid there its bad.
The green stripe is the most common, the colours mean different spring tensions ie the softer the spring the lower & softer the shift points . By adjusting the screew out your allowing the vacuum to act more on the modulator . I use all green stripe in the 400 and 350 . Try not to adjust it too much a couple of turns is ok. You need good vacuum make sure your pump and lines are in good shape !!!!!!

 

[edpdx]

rnd Sarge,

Thanks for the help. The one I have is Fram FM2321 (GREEN stripe). I drove my M1009 on the flat streets tonight after traffic cleared. My shift points are at 21 MPH for 2nd and about 40 for 3rd!

The modulator instructions say to turn the screw in 2-4 turns (2 at-a-time) and see if this helps "Slippage and 'soft shifts'". I'll try this in the morning. What is the best way to get the shift points lower- what speed should they be set at?

 

[ralbelt]

Ed I would replace all the rubber vac hoses before I start adjusting. If you are losing vac it will shift hard and late.

First rule of owing a CUCV. If it's rubber replace it, if it's electrical clean it.

 

[rnd-motorsports]

And the shift points are really close to where they should be. everybody likes them a little dif. turning the screw in will raise the shift points a tad also if you change out the filter and want better shifts if you can still get it in your area type F trans fluid its cheaper than say bm trick shift fluid the dif in it over dextron is the dextron is smother the type f will firm up the shifts more grit if you will just a little info

 

[edpdx]

I have already replaced the rubber on the modulator to VRV- both ends. The two rubber hoses that come from the VRV, and the one that connects the lower VRV to the pump at the top rear of the engine. Now I know any vacuum leak affects driveability somehow; but as far as the transmission shifting goes, these would be the only rubber hoses that would affect the shifting or slippage in this circuit right? I will look for any other vac hoses to switch out though.

I am thinking I should try to get the points lower as the tranny seems strained for waiting so long to get into 3rd gear- its coming in at about 40 MPH. What are considered advantages or disadvantages to higher/lower shift points?

 

[rnd-motorsports]

Any vac leak you have in any line anywhere will change the vac to modulater ,more so becouse of the way you are making vac on this engine need to check all lines and yes you could use to lower the shifts a little I would back the modulater out a tad not screw it in backing off will make the modulater easyer for the vac to pull on and the shifts to be sooner. will look in my trans book to find the ratings on the stripes and post them if I can find them cant remember the dif colors been ahwile and memory not what it use to be!

 

[edpdx]

I'll give your suggestion some thought. Per the direction sheet included by Fram: "To eliminate soft shifts or slippage, turn the modulator adjusting screw in a clockwise directions two (2) full turns..."

?????

Ed