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Just did a brake job the other day, and it brought a steering issue to light. I have power drums all around and when I made some passes in reverse to let the auto-adjusters do their thing, a loud pop would come from the front left wheel after applying the brake fairly hard, then letting off (not during brake application). It did not do this a month ago when I was trying to auto-adjust the rears, this just started.
It's the exact same sound that I get when making a left turn, especially at low speeds when there is greater stress on the steering system. At a certain point in the steering wheel's travel, a "pop" can be heard from the front left of the car and felt through the wheel. Again, usually only when turning at parking lot speeds, a lot of the time it does not happen when navigating a turn at 20 or so. No anomalous wheel scrubbing or indication of the two front wheels falling out of alignment with each other, thankfully. The car turns as smooth as you please, but that pop sure is unpleasant to feel and hear.
It does not happen over bumps, the entire car is smooth and quiet through dips and over speed bumps, and even when braking fairly hard going forward, as I found while seating the new shoes.
While raising the front end again to investigate a brake drag issue on the front left drum, I shook down the suspension and found everything to be tight, except where the pitman arm meets the centerlink. There's noticeable play at that connection, though it will still require some prying apart when I go to fix it.
So my question is, on these cars, which part is the "wear item"? The center link, or the Pitman arm? Both? Or is there a bushing that can deteriorate and needs replacement? I'd like to get this fixed ASAP so I can justify spending the money to renew the car's AC system for this summer... Can't really justify that to myself if I have to park the car because I don't feel 100% confident in the steering system.
That's about what I thought from looking at it. That's good news, because as with my '69 Chevy nobody seems to have pitman arms readily available for this car.
Is there anything I can do to remedy this except replace the entire center link? My search did turn up a site offering up a new one when I considered this a little while back, but it'll run a couple hundred for one of those assuming it really is the correct part.
Guess I'll have to get some measurements together to make sure I get the right one... I see one for a 1965-1968 Dynamic 88, as well as one for a 1965-1970 Dynamic, despite that not being a model anymore by '68 or '70.
That kinda bites, but I guess it won't need attention for a long time once it's done. Thanks for letting me know!
That's about what I thought from looking at it. That's good news, because as with my '69 Chevy nobody seems to have pitman arms readily available for this car.
That's because the pitman arm doesn't wear out, so there is no market for replacement parts. You need to replace the center link.
Yup, that's what I found on the Chevy... The shop that I took that car to back before I knew my way around cars very well insisted that the pitman arm itself was worn out and that they could not align it until a new one was found to replace it... Which they couldn't help with, naturally.
Turned out they were full of hot air in more than one way, I took it to another shop that aligned it without any fuss and they didn't find any problematic slop in the steering.
I was just making sure since I've been fortunate enough that this is only the second car I've owned with a steering system worn this badly. Even then, last time it was only tie-rod ends, so this is the first time I've had a worn-out center link on an old car. But yes, it makes sense that the center link's stud is the wear item.
Thanks, Eric. Part #s always help a ton. I'll take a look at mine and compare.
Also, I've noticed that a lot of center links require measuring the stud diameter on the old one to ensure compatibility. Would the wear on the old one give me a bad reading when measuring the stud, given that it's worn enough to be loose?
Ah okay, thanks. Good to know all this before I actually tear thing out of the car to measure it up, I figure. Looks like regardless of stud diameter I can probably get the part about $50 cheaper than I thought initially, so everything's not looking too bad.
Expensive as it is I'd rather drop the money now than park the car again, or wind up losing my steering or, probably most likely, wind up messing up the pitman arm with the link stud moving around loose like it is. Not sure how much of a possibility that is, but I hate taking chances.
For both the full size applications and the Cutlass / 442 -- it IS the Center Link and Idler Arm that the pivots lose their tension -- they are the wearable items -- in both cases the Pitman Arm is "two holes" -- one on the center link and one on the gear box -- so there is nothing to Naturally wear (not including bend or break from dopey tow truck drivers!!)
The 1968 - 1972 Olds Cutlass uses a DS749 Center Link -- and I have U.S.A.
made ones for $ 60 and U.S.A. made Idler Arms for $ 35.
Should be the best prices on the planet .....
You are welcome to call -- Craig -- 516 - 485 - 1935 ... New York...
Hi Craig, thanks for the part info. Unfortunately I'm working with a '67 Delta full-size, as far as I can tell center links for the B-body cars run a bit more than for the Cutlass. Oh well. That's the price I pay for being a sucker for big cars.
Still have to gather the motivation to go under and check the idler arm and disconnect the link at the pitman arm to mic the stud to see if I've got a Saginaw or TRW setup. Given that it's a power-assisted steering system I'd assume it's the Saginaw link with the slightly beefier stud, but you know what they say about assumptions.
Sorry, I thought for some reason you had a 72 Cutlass. The part number for your Delta I believe (dependent on length) is 25789 or 25790. Its available through your local napa or autozone stores. Theres some on ebay also. http://www.ebay.com/sch/i.html?_odkw...+link&_sacat=0
No problem, my bad for not stating the application or providing what I've got in my profile or sig. lol
I'll probably do that now, before I forget.
Those part numbers are spot on. Kanter says to measure the end of the taper closest to the threads on the stud, Saginaw should measure .587" and TRW should measure .556"
Now that I've got a micrometer on loan I might go ahead and get that done and over with tonight, or it might wait until tomorrow. I'm also fighting to find a solution for a stretched parking brake cable that can't/won't adjust any further, so I'm a little embittered towards doing cramped work under the car at the moment, but we all know it's gotta get done somehow.
we all thought you were talking 1968 - 1972 Cutlass / 442....
You are NOT a sucker -- you are a lover of a MAJESTIC Full Size OLDS!!!!
More points to you -- not less!!!!!
And in 1965 - 1968, there were two different companies that supplied Olds
with Front Ends:
The Light Duty -- TRW -- .556 taper diameter, indeed, and those part #s
are DS734 and 18652 TRW -- and I have them both N.O.S. U.S.A. made.
The Heavy Duty -- Saginaw -- .587 taper diameter, indeed, and those part #s are DS735 and 18653 TRW -- and I have them both N.O.S. U.S.A. made.
Rather than go with the repopped overseas junk -- I can give you U.S.A. quality for less than the price of the garbage!!!!!!
98 % are "Saginaw" which is the Heavy Duty -- but they are NOT interchangeable -- you HAVE to use what is on the car.
And, sadly, they ARE more $$ than GM "A" body -- but I'll take care of you, best I can......
Yes, sorry again about the confusion! Completely my error.
Thanks for the kind words, I do love my big boat of a car, regardless of overall popularity or parts availability.
I separated the link and measured it today. Holy smokes, that stud was loose in its socket. Scary to think that I was driving on that. I noticed that the zerk is busted off, which might explain its heavily worn condition compared with everything else. All other steering parts are good and tight, idler arm included. Wonder how long the pitman stud's ball joint has been exposed to the elements and neglected on grease.
It appears to be a Thompson front end. The micrometer fit neatly around the upper taper when locked to .556, didn't touch any part of the stud when it was out to .587. Guess I've got a little bit of an oddball car.
Craig, what's a NOS TRW link run? I found a repro for $178 out the door, so it looks like that's the price to beat... Would love to go NOS if possible. If it's not in the cards right now, then I'll probably go repro and then swap to NOS once I'm capable. Kind of on a shoestring budget with all the other attention all my cars have needed recently. Currently tending to an old Cadillac with an ornery starter, a Chevy which needs a complete tune-up to meet emissions standards again, and a Buick that's developed a tendency to overheat, so I'm stretched kind of thin for must-replace parts like this right now.
We kinda' use the repop price -- which is an acceptable price, at least (just
their quality is NOT good -- which is why it is definitely smart to use the
N.O.S. -- 1 time ONLY!!!!!!!!)
Let's see which set up you have:
The TRW // Light Duty // .556" diameter or
The Saginaw // Heavy Duty // .587" diameter....
As I Had indicated, I'll take care of you best I can --
I should be able to get the price under the $ 178 price, for sure; how much
under it -- let me see which set up you have and, of course, how and for how much I acquired what I have -- that will dictate what price I can give
to you.
Thanxxxxxx, Craig
No lie... to this day.. it has always been a pain in the butt!!!
Of course, General Motors didn't care about "problems down the road"
and who it would inconvenience, and they sure as heck didn't think these
cars would be around 40 years later!!!!
Their business was pumping out new cars -- and sales exceeded what they
had originally thought -- and they needed these companies to work fast
at "spitting out" AS FAST AS THEY COULD -- to get more cars rolling
through the Assembly Lines at the various Factories.....
Once again, nobody cares about "You and Me"...............
Hmm, mine does measure much closer to the .550" thin Saginaw spec, assuming that's a stud measurement. Nowhere near .580".
Here are a couple photos of the one in the car, from the left and from the right. Mine does not stick out a bit at the ends like the "fat" Thompson example you show, and it has/had the straight zerk fittings of a Saginaw... Though I'm not sure if those could possibly be interchanged somehow. I notice the shape of each end is a little bit different, a bit more tapered. Not sure if that indicates anything.
I've discovered a much easier way to tell a "Saginaw" steering system from a Thompson, TRW, alternate"etc. system.
Wire brush all the crud off the bottom side of the pitman arm(the one attached to the steering box). There will be a forging number on the pitman arm.
If the forging number has seven digits and starts with 56 it's a Saginaw.
If it has six digits then it is a Thompson, TRW , or alternate system.
Been a while, I struck a deal with Octania for a used TRW link and have been awaiting its arrival.
Tried to install it today, everything looked identical to the link that's under my car complete with all the same bends and tapering on the ends of the link bar, but the stud taper turned out to be larger. I was under the impression that all TRW links were one stud size and all Saginaws were the other, so unless the unit in the car has been modified, I guess the shape of the link bar is not a safe bet when determining steering system type.
Does look like it's been in there for decades and the tapers fit the idler and pitman arms perfectly, so I'd trust that this is the original unit.
Good tip on checking the part # on the pitman arm, Charlie. I brushed some crud off mine and looked, and surprise surprise, the part number on mine is five digits, not six or seven... I'll have to go back under next time I work on the car to get the exact number, but the format is ##-###. First two numbers are 43, I believe.
So now I'm weighing options. Considering that this seems to be a super-rare steering variant, I'm not likely to find another link that'll fit these arms, so I'm going to pull the entire bar out soon and see if the tie rods will fit the TRW bar. If so then I may look into modifying the existing arms to accept the bigger stud, or put out a want ad for a TRW pitman and idler arm.
I would opt for a Saginaw link with the thinner studs, but I'm not sure if the considerably different bar geometry would allow me to install it in place of a Thompson link without issues, and am not really willing to spend that kind of money blindly gambling on that.
Thinking about this dilemma, I'm actually beginning to entertain the idea that someone may have long ago modified a thick-stud bar to fit a slim-stud system.
A possible tell is that holding the steering wheel centered has always caused the car to steer slightly to the left, though without driver input the car wouldn't try to pull to the left. The steering wheel would find its natural center about 1/8 turn or so to the right.
An idea: If the current bar has different/shorter lengths beyond and between the tie-rod connections, then it might be that with my setup the steering wheel has to be steered to the right a bit in order for the wheels to actually be straight, since if equipped with a standard straight slim-stud bar from the factory the tie-rods would have been adjusted for the straighter link instead of the one that's in there now... Correct me if I'm wrong here, please.
From what I've seen it's not readily apparent if the tapers on this original bar have been ground down to the slim size since the tapers themselves actually fit quite well in the arm sockets, so now I'm trying to figure out if a regular slim-stud link would drop in without any issue. It seems like the only difference it would make would be to alter the height of the inner tie rods a little bit and to alter or possibly fix the relationship between the steering wheel and the front wheels, so it may be possible.
If this link was modified then maybe that's how the pitman ball joint got damaged in the first place, and the modifier either decided to use it anyway or had no other choice.
If I need a slim-stud drag link instead, I figure I'll probably bite the bullet and pay whatever it costs for an example of one, and return the thick-stud link I currently have rather than modify it or the arms. I'll continue to investigate.
Thinking about this dilemma, I'm actually beginning to entertain the idea that someone may have long ago modified a thick-stud bar to fit a slim-stud system.
Very doubtful.
A possible tell is that holding the steering wheel centered has always caused the car to steer slightly to the left, though without driver input the car wouldn't try to pull to the left. The steering wheel would find its natural center about 1/8 turn or so to the right.
This is an alignment issue. The crown in the road can also cause this
An idea: If the current bar has different/shorter lengths beyond and between the tie-rod connections, then it might be that with my setup the steering wheel has to be steered to the right a bit in order for the wheels to actually be straight, since if equipped with a standard straight slim-stud bar from the factory the tie-rods would have been adjusted for the straighter link instead of the one that's in there now... Correct me if I'm wrong here, please.
Again, an alignment issue.
From what I've seen it's not readily apparent if the tapers on this original bar have been ground down to the slim size since the tapers themselves actually fit quite well in the arm sockets, so now I'm trying to figure out if a regular slim-stud link would drop in without any issue. It seems like the only difference it would make would be to alter the height of the inner tie rods a little bit and to alter or possibly fix the relationship between the steering wheel and the front wheels, so it may be possible.
If this link was modified then maybe that's how the pitman ball joint got damaged in the first place, and the modifier either decided to use it anyway or had no other choice.
The wear is normal and I doubt someone went through all this trouble to change drag links. Most often, they would just change all 3 parts, idler arm, drag link and pitman arm.
If I need a slim-stud drag link instead, I figure I'll probably bite the bullet and pay whatever it costs for an example of one, and return the thick-stud link I currently have rather than modify it or the arms. I'll continue to investigate.
Let's back up a little
What is the year and model of the car in question?
-now- I notice your name implies 1972 and the car shown appears to be a Delta or 98.
Your profile lists a "1967 Delta 88 Custom Holiday Coupe" which looks like the pic I guess.
The drag links I have shown thus far are the earlier rear steer 65-70 types.
If your car is 71+ that would explain the problem. I do have such parts cars but nothing extracted at this time. It might be as easy as getting a compatible part.
Last edited by Octania; March 17th, 2016 at 06:11 AM.
Doubtful, yes, but if there's one thing I know it's that nobody's truly seen everything when it comes to hack-job car repairs. Seems nobody's seen a mismatched link/stud combo like this before, either.
Not a road crown issue, I'm aware of and have tested for that. Alignment issue, sure I buy that since I've had similar alignment issues on other old cars but then none of them have had busted drag links.
The particular issues here strike me more as damage or rapidly accelerated wear than regular wear, but yeah it is more likely that it's just worn that bad due to total lack of lubrication and being open to the elements.
If the two bar types are interchangeable, stud sizes notwithstanding, then yes, looks like I'll be going with the other link type.
Let's back up a little
What is the year and model of the car in question?
-now- I notice your name implies 1972 and the car shown appears to be a Delta or 98.
The drag links I have shown thus far are the earlier rear steer 65-70 types.
If your car is 71+ that would explain the problem. I do have such parts cars but nothing extracted at this time. It might be as easy as getting a compatible part.
Hmm... My car year/model should be showing up in my sig. It's a '67 Delta full-size, rear steer. The part received was identical except stud size, so a '65-70 drag link with the thinner studs should be the ticket... Was under the impression that the two steel bar shapes were not interchangeable but it seems that that may not be true.
Edit: Unless the pitman and idler arms are angled or shaped differently between Thompson and Saginaw (no clue), in which case the easiest thing to do may be to acquire arms meant for the bar with the big bends and thick studs.
But if the arms are all shaped the same and simply have bigger or smaller tapers bored for the different studs, then the other link design may well drop right in.
Last edited by Supernaut72; March 17th, 2016 at 06:41 AM.
So, we seem to have developed a better ? method for discerning Type T from Type S tapers, using common tools.
With one of each handy, I got out the metric wrenches and found that by fitting the open end [or 6-pt box end might work] onto the stud, the following was observed:
Wrench - Slim Sag. - Thick Thompson
14mm - fits Small End of tapered part - Fits over Threads only
15mm - fits halfway down the taper - fits Small End of tapered part
16mm - clears the entire taper - fits halfway down the taper
17mm - Clears with extra room (N/A) - clears the entire taper
It looks like an easy way to sum that is
using 16mm = 5/8", if it clears the entire taper it is S type
if it goes halfway down the taper, you have a T type
Hey oldolds, thanks for the offer! Fortunately things pulled together without too much fuss and the steering issue is resolved. More just patience than anything.
So, status update: Got the other link design with the slim studs, and it fit right in. Many thanks to Octania for the link. So for the record, the two link bar shapes/profiles do seem to interchange as long as the stud sizes match, which may be useful info if anyone else has/had a weird bar/stud hybrid link like mine.
Once complete, I immediately noticed that the reverse clunk was still there, turned out an upper control arm bushing had fallen apart and was reduced to the outer shell and inner sleeve
Spent a long night replacing that, and while getting the control arm bolted back into place I considered omitting the camber shims to correct the severe inner treadwear issue the front left tire was encountering, while also pondering a quick fix for the pulling issue mentioned above to make things bearable until I could schedule an alignment.
Well... While some friends and I were analyzing the oddly worn front-left tire all around before making any alignment decisions, we found that it had suffered pretty gnarly bead separation, the tread was extremely lumpy and deformed at a particular spot. Swapped front for rear and kept the alignment exactly as I had found it, and sure enough the pull vanished instantly. Went first thing this morning to have the tire swapped with a good one that the car previously wore.
The cocked steering wheel isn't fixed, but I guess some careful tie-rod adjustment will take care of that. Sure is off-center by an irritating amount. I would think it's not that hard to center a car's steering wheel before aligning the wheels, but considering the huge amount of play that may or may not have been in the steering at the time of alignment, I can't be too mad about it.
Anyways, long story short, the car's in much better health now. A big thanks to the Classic Olds community for help and guidance provided, definitely made this whole saga a lot more feasible to get through.
Last edited by Supernaut72; March 30th, 2016 at 03:47 AM.
And, now we have a handy way to discern T vs S type bar with just a 15mm or 5/8=16mm wrench!
Now, if you can get this straight. To prevent the spread of mis-information.
The Saginaw center link ends are the THICK ones (.587 diameter) and the thin (.556 diameter) studs are Thompson.
Reference the page that I scanned below from the Fusick Automotive catalog.
I still say the easiest way to tell a Saginaw from a Thompson equipped car is to look at the forging number stamped on the pitman arm. A seven digit number beginning with 56 is a Saginaw. Anything else is a Thompson ,TRW etc.
You don't have to disassemble anything.
February 27th, 2016, 01:40 PM
