F40H.D. vs. F41

what exactly is the difference between the F40 and F41 suspension options on the 80's caprice sedan.
specifically the 84' sedan.
i was looking at a sales brochure and was just curious what qualifies as Heavy duty versus Sport
seems like stiffer sway bars would be a sport part, but could also qualify as heavy duty since they were standard on the front anyway. stiffer shocks are definetley a sport part, but could also be heavy duty if the valving was geared more towards hard use on rough pavement...

i'm confused
:screwy: :banghead:

F40 Suspension System, Heavy Duty Front and Rear
F41 : Suspension System, Front, Rear, Firm Ride, Handling


F41 has rear anti-sway bar.

nvm my post, silicon nailed it.

So, what do I have on my '84? (or did I used to have when it was stock) I dont have a sway bar on the back, only on the front.

So, what do I have on my '84? (or did I used to have when it was stock) I dont have a sway bar on the back, only on the front.

See above. It's probably F40, but the RPO list/SPID label would clarify that. 1984 should have had a white/gray RPO label in the trunk, and may have also had the boilerplate on the firewall (I believe that was the transition year in most assembly plants).

What you have is mush. That's great if you're just boulevard cruising. If you want a little more compliant steering and ride, you might want to look at new springs with the same height but a higher rate, especially since your springs are 20+ years old. Think about a larger stabilizer bar up front, like BMR or Hotchkiss F-Body 1½" types (with new bolts and new end links), and installing a rear bar. Some station wagons had a large rear piece, but they aren't anywhere as stiff as the F-Body types. A fresh set of monotube shocks with tighter rebound control will help. And make sure you have a full compliment of body mount bushings (see Scott Mueller's article at http://www.theherd.com/articles/bushings.html).

i was looking for maybe a list of parts for each one that was bolted on to qualify the extra cost of each.
mine has neither, but i was wondering what was in the packages, and what the differences were.

As for my suspension, I've replaced the entire thing minus some bushings and body mounts. The springs were replaced in the rear with a variable coil spring, which is supposed to take weight better, and the shocks have been replaced with Monroe ltd lifetime shocks. Its nothing special, but It helped out big time having replaced the near 23 year old suspension. They've been holding up a lot of weight for a long time. Im not TOO worried about the handling... I mean well, it doesn't even compare to the handling of a newer car, but the ride is smoother than ANY new car I've ever ridden. Don't get me wrong, new cars have a smooth ride, but its a different kind of smooth. As for a rear stabilizer bar, I heard that stabilizer bars can take away from the smooth ride, and don't do as much on a solid axel as they do on an independant suspension. Just my :2cents:.

lets try it this way:
i'm a prospective buyer of a brand new 84 caprice classic, and you are a salesman trying to sell one of the last three on the lot before the end of the 84 model year. one has an F40 suspension and one has an F41. the other has the stock, no options suspension.
you are trying to sell me the F41. (more expensive)
i am asking you why i want to spend the extra $49 and what it will get me.
what is in it that is better than the $26 HD suspension or the free stock suspension.
SELL ME THE CAR.
i want to know the parts involved in the extra cost

Well, the F41, as on a 9C1, comes with Bilstien shocks, stiffer springs, and that rear sway bar. It gives a rougher ride than the pillow-soft stock suspension, but carries the corners where the stock won't. The rear sway bar in conjunction with the valving on the shocks helps to keep the car more level during cornering and helps keep the tires on the road, where they belong.

I'd get the F41 suspension, if no other reason than for safety reasons - at high speed and when the road is wet or during other adverse conditions, it's nice to know that the tires will hold the road as good as they can.

Now thats one heck of a sale's description right there! :grinyes:

so basically, F41 is code for 9C1?

so basically, F41 is code for 9C1?

I believe it was also on some later model Broughams, 1986 and newer.

Will the front F body sway bars fit on the front of a B body car? I just saw a 80's iroc z front sway bar in the wrecker. Looked like a fairly stout piece.

it should if the lengths are the same.

CD smalley or someone wrote a really good thread on how to make caprices handle better, and outlined all the parts that fit.
its called how to make a b body handle on a budge or something like that

Found it:

http://www.automotiveforums.com/vbulletin/showthread.php?t=321620

However, I have a few 9C1 rear sway bars and found there are two different attachment methods:

The earlier (I'm guessing 91-93 and before) sway bars attach to a short channel with two bolts through the holes in the sway bar, then this channel is slid into the lower control arm and fastened with two self tapping bolts from each side. The channel is still available from GM as I bought them a few months ago. This method of attachment will work for any B (and C?) body sedan (not wagon) from 1977 and up as the lower control arms have the required holes to fasten through to the sway bar mounting channel.

The second method (from 94-96?) will require a change on lower control arms as the same sway bar as used above is attached with long bolts through the top of the lower control arm right throiugh the mounting holes in the sway bar. There are a couple of small steel brackets the keep the sway bar in place. Less parts required, which is probably why GM switched the attaching method.

Which method provides better handling? I don't know. But from all the rear sway bars I've seen in the wreckers, the second method is definatly better if you don't want your lower control arms rusting out, as the moisture can drain away. Of course if you undercoated your car from new, you won't be worrying about rusty control arms.

Are front springs something I could do in my driveway or is it better left to be done by a shop? my front shocks and springs are gone, everytime i hit a moderate bump the front bounces like 5 or 6 times before settling down, lol.

I might do impala ss springs and 9c1 shocks front and rear. I can order the shocks at wholesale from my work :devil:

You can do the front springs yourself provided that a) you have a lot of patience, b) you have access to a set of spring compressors, and c) you have lots and lots of patience.

I've rebuilt/replaced every single part of a car over the past twenty-five years, and there are two things that just aren't worth doing:

exhaust and ...
front SPRINGS :banghead:

That was on a 77 Cadillac. Since then I've found out it would have cost about the same as I paid for the springs alone to have the sping shop supply & install them. A few years ago I had my 73 Buick Centurion done all around for CDN$350.00 out the door.

Rear springs are a piece of cake though. I replaced mine a few months ago with moog variable rate springs, and just took them out again on Sunday afternoon to install Monroe Sensatrac coil over shocks. Regular shocks are easy with the springs in, but coil overs really need to have the spring removed as you don't have straight access to the nut/bolts at the top as with the standard shocks.

I believe it was also on some later model Broughams, 1986 and newer.


yeah, my 88 LS had a rear sway bar... wish i still had that car :banghead:

Why did Chevrolet list a "GU4" as well as a "G92"? Both option codes refer to the rear axle / differential: the former is for "3.08", and the later is for "performance axle". This is as clear as a bowl of mud.

My '89 Caprice w/ a F41 suspension option, lists a "GU4" as well as a
"G92" on the "options sticker" inside the trunk lid. Since both of
those codes refer to the differential ratio, it seems like a duplication.
Anyway, it's rather unclear. Can anyone elucidate?

BTW, I tried Edmunds.com to learn more about my car. I entered
its VIN, and it came back claiming that is was an LS Brougham.
It is not----it's just a plain (though loaded) Brougham. So, in
other words, one cannot always believe what they're told,
regardless of the type of source of the info.

Nice 6.25 year old necropost!

The G92 might be a redundant code or an enforcement of the GU4 code.

Similar to transmission codes MX0 and MD8, which will often appear together, where MX0 is Merchandised, auto with OD, and MD8 is THM700R4/4L60.

G92 is the performance axle and GU4 is the axle ratio 3.08 f41 s the supension code and MW9 is for the 200 R4 tansmission. The Code for a Brougham LS is B6N 9C1 is the code for the police car only has nothing to do with a brougham 9C1 is a base model and will have a BL in the vin vs the brougham will have a BU in the vin and if 9C1 has a 4.3 v6 it have a vin code Z gas or fuel injection and if its the 7 code thats a 350 and the E is a 305 TBI. H code caprices are a 305 with a carb and thats 88 or less 89-90 are E codes only with the exception of 9C1. Also a 9C1 is the only car you could get a 5.7 l code 7 engine from the factory. I had an 84 caprice 87 classic and i currently own an 89 Brougham LS that i have had since 2000 for the most part all chassis parts from 1971 -1996 are generally the same shocks springs and arms ball joints and links. monroe coil overs are the best shock for a caprice in my opinon and the lower springs add to stibility and cornering quite a bit especially if you have the F41 package. one last thing the LS top of the line distintion was only from 87-90 all other LS designations are base model cars and you know you have the LS if you have the quarter top full vinyl tops are broughams only.

A few clarifications of the above post:

VIN code E (8th digit) is L03 305 (TBI), code 7 is L05 350 (TBI), code H is LG4 305 (Q-jet) and code 6 is LM1 350 (also Q-jet).

Also, the platform ran from 1977-1996, not 1971.

To GreyGoose006, as re: your post a while back:

No, 9C1 does NOT mean F41. 9C1 is a police car 'package', which likely includes the F40 heavy-duty suspension option --- which is DIFFERENT from the F41 sport suspension option... though there may be some common items for each of those two optional suspension packages.

This is a common misconception, unfortunately.

To renaldorae, I much prefer Delco stock, or Gabriel shocks over any Monroe.

To GreyGoose006, as re: your post a while back:

No, 9C1 does NOT mean F41. 9C1 is a police car 'package', which likely includes the F40 heavy-duty suspension option --- which is DIFFERENT from the F41 sport suspension option... though there may be some common items for each of those two optional suspension packages.

This is a common misconception, unfortunately.

To renaldorae, I much prefer Delco stock, or Gabriel shocks over any Monroe.

I think he was actually asking if the F41 came as a part of the 9C1 package, which is affirmative. I don't think he actually thought that if F41 was present, that it was automatically a 9C1.