My girlfriend's father (self-proclaimed Ford expert) told me that I needed to put some posi-traction rearend additive into my tranny to help keep the clutch packs from slipping. This seems kinda fishy to me. I was wondering if anyone here has heard of such a thing. He claimed it really helped out his 96 F150 and Grand Marqiuee (Crown Vic)
Thanks
Chris
Y2K F150 Harley package

 

That would be friction modifier, and add it to the rear differential when you change the rear lube. Your local Ford service center should have it for $4.00 or $5.00. I changed my own diff fluid and did not add it and the clutches would grab when going around a corner. Now that I have added it everything is much better. Remember your trany and your rear end are two different things.

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'97 F-150 4x4 4.6L Auto Off Road Moonlight Blue
Tow package, Westin Chrome Nerf bars, Color matched bug shield
Linex bed liner, Wizard Ultra White Headlights

 

The friction modifier is intended to help the clutch packs SLIP.

 

crown vic have a 5 speed transmission ? or do you mean the read diff. ? lol

 

I mean the transmission. He said to put this additive in the automatic transmission.

 

Well I would tell your "future father in law" that the clutch packs are in rear differential. By ford specs when you change the rear differential lube you are supposed to add a bottle of friction modifier. to help the clutches slip better when turning. You will not hear the clutches grab going around the corner. With out the modifier the clutches act somewhat like a posi rear end. I did not like the sound of it and added the friction modifier. Some people run without it for that reason. The down side is your clutch packs will wear quicker. I like the behavior with the friction modifier better. As far as I know all you need to add to the automatic transmission is the correct tranny fluid.

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'97 F-150 4x4 4.6L Auto Off Road Moonlight Blue
Tow package, Westin Chrome Nerf bars, Color matched bug shield
Linex bed liner, Wizard Ultra White Headlights




[This message has been edited by BERVINATOR (edited 02-23-2001).]

 

A properly maintained transmission needs nothing but ATF. Most of the automotive junkies that I know stay away from most additives. The friction modifier is not made to be used or mix with ATF. If it made it do anything, it would be slip; which creates more wear and heat(only reducing life).

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2000 F-150 XL, RC, LB, 5.4L, 4R70W, 3.55LS,
Class III tow, Payload #3, & Convenience pkgs.,
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Dynomax ultra-flow welded 3" cat-back w/ 3" Y-pipe,
Hellwig front & rear anti-sway bars, Rancho RS 9000s,
Mobil 1, K&N oil filter.

 

Howdy Chris,

WEll I can't say I blame Da Father for wanting to protect his daughter (as in get rid of potential son in law)

Seriously, DO NOT put FRICTION Modifers into your tranny fluid. The best THanG you can do is change the tranny fluid at 12,000 miles intially, then every 15,000-20,000 there after.

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2000 F-150 Lariat, Flareside, Black, SC, FOxFO, 5.4L, 4R70W TranZ, 3.55 Limited Slip Rear Axle, Garmin Street Pilot Color GPS, Bed Rug, ExTang Saber Tonno, CatchALL Floor Mat's, VentShade Visors, Limo BLaCK Tint'd Windows, PIAA Platinum Super White Headlight Bulbs with XTra Technology, FLoWMaSTer 40 Series MuFF, Mobil 1 5W-30 and Motorcraft 820-S Filter, SuperFReaKiN - FLiPCHiP Cal'd for Regular and Premium FueL,

Soon..............

AiRaID FIPK, Expedition Front and Rear Sway Bars, F-1 HooD, P305/75/R17 BFG KO's, 3" Body LiFT

www.tnugent.com/

 

Chris,
I have heard of doing this. Your father in law to be misunderstands the reason it is done. Y2k is correct in that this lowers the coefficent of friction of the lube allowing more slip. It is used as a band-aid in transmissions which are prone to torque converter shudder (read: Ford, Chrysler) to prevent or lessen the shudder. On Fords the shudder can usually be eliminated by frequent trans fluid changes.


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97 XLT S/C Long Bed 2wd, 4.6 Romeo, 4R70W trans, 200,000 miles

 

Bent 6, you've got a lot of miles on your 4.6/4r70w. My ride has 36000 miles vs your 200 K. Any major problems ? If not what words of wisdom do you have ? Have you use 5w 30 for these miles ?

A bit off topic but back to original thread: The difference between Dexron and Mercon and Mercon V ( aside from the later being syn) are the different frictional characteistics of the oil against the clutch facings. Ford techs dont advise switching Mercon to Mercon V because later transmissions have directional clutch paks, Earlier trans do not. On top of this the clutch facings are fully soaked and leached through with old oil. Putting posi friction modifier into your trans is really asking for trouble. Solve the problem (instead of treating a symptom) = heat oxidizing the oil...install a trans cooler keep the trans temp < 140 degrees and the trans oil will last indefinitely based on my experience with industrial applications

Regards
Dave



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97 F150 4x4 Ext Cab Long Box 4.6L Auto, stock, in showroom condition Oxford White/Gold BedRug

 

Chris,

Your G/friends Dad is probably 85% correct. And no matter what a few of the previous uh "Mechanics - Techs" may have said it's obvious they are ignorant on the subject, which is ok we're here to learn. But I'm hoping you didn't tell her dad that an auto-trans doesn't have clutch packs.

The discs, steel plates, piston and return springs as an assembly are known as a clutch pack.

Bent6 is steering you right.
However, if the issue persist even after a fluid change you will need to add some GM posi-clutch additive to the tranny. With the clutch packs being submerged in fluid they can actually slip (shudder) over time and the additive will provide it with the needed friction. Trust ol'dad he may be an expert!!

 

Scott, do you realize that this thread died over 8 YEARS ago?

I would NEVER put limited slip friction modifier in an AUTOMATIC TRANSMISSION. If there were an advantage to doing this, wouldn't you think the manufacturers would recommend it? Under certain circumstances, there ARE additives made for automatic transmissions that DO help, but that's not one of them.

NOW - back in 2001, when this thread was active, there was still Mercon. Ford has since discontinued it, replacing it with Mercon V, which DOES have different friction characteristics. I do believe that it does take care of some issues in the earlier transmissions.