OPINION OF THE COURT
This appeal requires us to decide if a sufficient quantum of admissible evidence was presented at trial to establish a prima facie case of negligence. We determine that plaintiff-appellee Aloe Coal Company did not present sufficient evidence of causation to submit its negligence claim to the jury.
We also visit again the issue that was before us in
Pennsylvania Glass Sand Corp. v. Caterpillar Tractor Co.,
When the damages issue was here before we recognized that Pennsylvania had not yet settled the question of whether injury to an allegedly defective product itself was compensable in tort. We identified the majority rule, set forth in
Seely v. White Motor Co.,
In the context of admiralty law, the Supreme Court in
East River S.S. Corp. v. Transamerica Delaval, Inc.,
— U.S. -,
I.
In 1977 Aloe Coal Company, a strip mine operator, purchased a tractor shovel manufactured by Clark Equipment Company. After Aloe extensively used the tractor shovel for approximately five years, it was destroyed by a fire of unknown origin. Commercial Union Insurance Company, Aloe’s insurer, reimbursed Aloe for the full amount of the loss and subsequently filed suit against Clark in the district court based on three theories: negligence, strict liability, and breach of warranty. The district court exercised diversity jurisdiction over the subject matter of this action pursuant to 28 U.S.C. § 1332, and applied Pennsylvania substantive law to the controversy. The case went to the jury on the negligence theory only, and in response to special interrogatories, the jury found Clark sixty-five percent negligent and the plaintiffs thirty-five percent negligent. Judgment was entered accordingly.
On May 16, 1986, Aloe filed a motion to mold the jury verdict to include delay damages under Rule 238, Pa.R.Civ.P. Thereafter, Clark filed a motion for judgment n.o.v. or, in the alternative, for a new trial, which was denied by the district court on July 16, 1986. On August 12, 1986, Clark filed a notice of appeal from the July 16 order while Aloe’s May 16 motion was still pending before the district court. On September 29, 1986, the district court granted Aloe’s May 16 motion; Clark did not file a new notice of appeal.
II.
As a preliminary matter, we address
sua sponte
the issue of our appellate jurisdiction. The matter that gives us reason to pause is the pendency of Aloe’s post-judgment motion in the district court at the time Clark filed its only notice of appeal. If that motion was a Rule 59(e), F.R.Civ.P., motion to alter or amend the district court’s judgment, Clark’s notice of appeal would have been a nullity and appellate jurisdiction over this case would be absent.
Griggs v. Provident Consumer Discount Co.,
A.
The caption to Aloe’s motion described it as “PLAINTIFFS’ MOTION TO MOLD JURY VERDICT TO INCLUDE DAMAGES FOR DELAY UNDER Pa.R.C.P. 238,” and made no reference to the federal procedural rule under which it was submitted. In paragraph four, however, the motion recited that it was “being filed within the ten-day time period specified in F.R. C.P. 59(e) with respect to Motions to alter or amend judgments.” Even were we to take this recital to evidence an intent on Aloe’s part to submit the motion pursuant to Rule 59(e), it would not be controlling for the purposes of Rule 4(a), F.R.App.P. “The focus ... is on the function of the motion, not its caption.”
Turner v. Evers,
Aloe’s motion was for the purpose of adding delay damages to its jury verdict
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pursuant to a Pennsylvania procedural rule, Pa.R.Civ.P. 238. We previously have held that “a post-judgment motion for Rule 238 delay damages is in the nature of a motion to correct clerical mistakes in judgment under Rule 60(a), F.R.Civ.P.”
Bob’s Drag Chutes, 111
F.2d at 55. We explained the reason for this characterization in
Hayden v. Scott Aviation, Inc.,
B.
As a motion under the aegis of Rule 60(a), Aloe’s post-judgment motion for delay damages had no effect on the time for appeal under Rule 4(a), F.R.App.P.
See Bob’s Drag Chutes, 111
F.2d at 55 (citing
International Controls Corp. v. Vesco,
III.
Moving to the merits of the present dispute, Clark first contends that the district court erred in denying its motion for judgment n.o.v. because Aloe did not carry its burden of proving that Clark’s alleged negligence was the legal cause of the accident.
A.
In examining the district court’s denial of appellant’s motion for judgment n.o.v. or, in the alternative, for a new trial, we are required to “ ‘view all the evidence and inferences reasonably drawn therefrom in the light most favorable to the party with the verdict.’ ”
Marino v. Ballestas,
B.
Before we evaluate the evidence in light of this standard, we must review the legal components of Aloe’s claim. In a negligence action under Pennsylvania law, “[t]he plaintiff has the burden of proving the negligence of the defendant as the legal cause of the accident.”
Rice v. Shuman,
*114 The actor’s negligent conduct is a legal cause of harm to another if
(a) his conduct is a substantial factor in bringing about the harm, and
(b) there is no rule of law relieving the actor from liability because of the manner in which his negligence has resulted in the harm.
Pennsylvania has adopted the Restatement analysis.
Vattimo v. Lower Bucks Hospital, Inc.,
The question of causation is ordinarily for the jury.
Ford,
C.
After a thorough review of the testimony in this case, we conclude that there was not sufficient proof of causation to allow Aloe’s negligence claim to go to the jury. Aloe’s theory was that “a fire originated within the ... 475B Michigan hi-lift tractor as a result of a ruptured hydraulic pressure line.” App. at 8a. Aloe contended that the ruptured line was due to Clark’s negligence in manufacturing the tractor shovel. Id. The critical question is whether Aloe supported its allegation regarding the cause of the fire.
Aloe relied solely on the testimony of one person to establish causation. He was Michael Drewnoski, a sales representative for Mendes & Company, whose position required him to determine the costs of repairing and replacing damaged equipment. Over Clark’s objections, the district court allowed Drewnoski to give expert testimony regarding the cause of the tractor shovel fire. Drewnoski’s opinion was that the fire was caused by a leak in one of the hydraulic lines. App. at 318a. This testimony presents the threshold question of whether Drewnoski was competent to serve in this expert witness capacity.
Guiding us are settled legal precepts. An expert witness must have such skill, knowledge, or experience in the field as to make it appear that his opinion will probably aid the trier of fact in his search for the truth.
Caisson Corp. v. IngersollRand Co.,
After carefully reviewing Mr. Drewnoski’s credentials, we conclude that the district court abused its discretion by allowing the witness to testify regarding the cause of the tractor shovel fire. Drewnoski was not an engineer. He had no experience in designing construction machinery. He had no knowledge or experience in determining the cause of equipment fires. App. at 300a. He had no training as a mechanic. He had never operated construction machinery in the course of business. Id. at 303a-04a. He was a salesman, who at times prepared damage estimates.
We are well aware of “the liberal policy of permitting expert testimony which will ‘probably aid’ the trier of fact.”
Knight,
D.
Aside from the testimony of Drewnoski, Aloe did not present any evidence from which a jury might reasonably conclude that Aloe’s tractor shovel fire was caused by a ruptured hydraulic line. Viewing the record in the case in the light most favorable to the plaintiff, we do not find a “minimum quantity” of evidence of causation. Accordingly, we conclude that the district court should not have submitted Aloe’s negligence claim to the jury. But this does not end our inquiry. We must now decide if Clark was entitled to judgment n.o.v. on this issue alone.
IV.
We are faced with circumstances in which the totality of causation evidence, minus the Drewnoski testimony, was insufficient to send the case to the jury. Under such circumstances, it is clear that in considering a post-trial motion for a new trial the court is free to consider the abridged record, that is, in this case, a reconstructed record that did not include Drewnoski’s testimony.
See Montgomery Ward & Co. v. Duncan,
The United States Courts of Appeals for the Fifth and Eighth Circuits, and the Supreme Court of New Mexico, suggest that although a truncated record may properly be considered in a motion for a new trial, the court must consider the entire record, replete with incompetent evidence, in deciding the judgment n.o.v. question.
See Dixon v. International Harvester Co.,
We have carefully examined the opinions from the Fifth and Eighth Circuits, and New Mexico, but regrettably we find no reasoned elaboration to support their thesis that “[i]n ruling on the sufficiency of evidence the trial court must take the record as presented to the jury and cannot enter judgment on a record altered by the elimination of incompetent evidence.”
Midcontinent Broadcasting Co.,
The closest to an explanation forthcoming in the cases appears in Midcontinent Broadcasting Co.:
*116 The subsequent ruling, after the verdict, that the expert opinion was not admissible after it had been originally received and considered by the jury, placed plaintiff in a relative position of unfair reliance. If plaintiff had been forewarned during the trial that such testimony was not admissible it conceivably could have supplied further foundation or even totally different evidence. Under these circumstances the grant of the judgment n.o.v. was not a proper remedy-
In any event, we are not required to resolve this issue here, and indeed, we prefer not to because the question was not addressed by counsel by brief or argument on appeal or in the post-trial motions. We need not meet this issue because we hold that, as a matter of law, the plaintiff was not entitled to the damages it sought.
V.
Our approach requires us to decide if fire damages to Aloe’s tractor shovel may be recovered by the purchaser from the vendor on a theory of negligence under Pennsylvania law. We exercise plenary review over this issue.
Universal Minerals, Inc. v. C.A. Hughes & Co.,
A.
It cannot seriously be questioned that, if presented timely, Aloe, the buyer of an allegedly defective product, and its insurer had rights and remedies against Clark, the manufacturer, under contract and Uniform Commercial Code precepts. Nor is it disputed that Aloe suffered neither personal injury nor property damage other than loss of the purchased product. Since Aloe sought damages only for the replacement cost of the defective product, its loss was purely economic.
See East River S.S. Corp. v. Transamerica Delaval, Inc.,
— U.S. -,
B.
In
Pennsylvania Glass Sand Corp. v. Caterpillar Tractor Co.,
We applied the
Pennsylvania Glass Sand
rationale in
East River S.S. Corp. v. Delaval Turbine, Inc.,
Our conclusion in
Delaval Turbine
was affirmed by the Supreme Court for different reasons in
East River S.S. Corp. v. Transamerica Delaval, Inc.,
— U.S. -,
The intermediate positions, which essentially turn on the degree of risk, are too indeterminate to enable manufacturers easily to structure their business behavior. Nor do we find persuasive a distinction that rests on the manner in which the product is injured. We realize that the damage may be qualitative, occurring through gradual deterioration or internal breakage. Or it may be calamitous____ But either way, since by definition no person or other property is damaged, the resulting loss is purely economic. Even when the harm to the product itself occurs through an abrupt, accident-like event, the resulting loss due to repair costs, decreased value, and lost profits is essentially the failure of the purchaser to receive the benefit of its bargain — traditionally the core concern of contract law.
— U.S. at -,
C.
Because our jurisdiction in this case is founded on diversity of citizenship, we are bound to apply Pennsylvania law to the present controversy.
See Wilson v. Asten-Hill Manufacturing Co.,
We understand completely that the East River holding is not binding on Pennsylvania courts, because the Supreme Court’s decision was based on an interpretation of federal admiralty law only. The United States Supreme Court is supreme in matters of federal law; the Pennsylvania Supreme Court is supreme in matters of Pennsylvania law. Nevertheless, we conclude that the United States Supreme Court’s analysis is so persuasive that it will be followed by Pennsylvania courts.
D.
In reaching its decision in
East River,
the Court emphasized five considerations: (1) when the defective product injures only itself the reasons for imposing a tort duty are weak and those limiting remedies to contract law are strong; (2) damage to the product itself is most naturally understood as a warranty claim; (3) contract law is well suited to commercial controversies because the parties may set the terms of their own agreements; (4) warranty law sufficiently protects purchasers by allowing them to obtain the benefit of their bargain; and (5) warranty law has a built-in limitation on liability, whereas tort actions could subject manufacturers to an
*118
indefinite amount of damages. — U.S. at -,
In East River, the Court also focused on the realities of the marketplace and recognized the quid pro quo of modern arm’s length commercial transactions of the character now before us. In the case before us, the business relationship was between a coal mining company, an experienced purchaser and user of excavating equipment, and the manufacturer that supplied the equipment. The Court noted that under similar circumstances, the manufacturer could restrict its liability by disclaiming warranties or limiting remedies under sections 2-316 and 2-719 of the Uniform Commercial Code, 13 Pa.Cons.Stat. §§ 2316, 2719. In exchange, the purchaser bargains to pay less for the product.
On the basis of the foregoing, the Court arrived at a public policy judgment for cases of this type, concluding that it preferred the built-in limitation on damages in a warranty action over the open-ended and indefinite damages available in tort. In the former, the limitation stems from foreseeability and privity; in the latter, “[i]t would be difficult for a manufacturer to take into account the expectations of persons downstream who may encounter its product.” — U.S. at-,
The Court’s opinion was not a paste and scissors job that set forth the diverse holdings in myriad cases and then arbitrarily opted for one view over the others,
see, e.g., Pennsylvania Glass Sand,
764 (1986) (“The time has come to identify exactly what fundamentals underlie the controversy in each case, and to isolate which is the governing branch of the law’s family tree. Our first step in any legal argument must be to look at the tree’s trunk and main branches, rather than to concentrate on new twigs that continually sprout in all directions.”). For these reasons, we are convinced that the Pennsylvania Supreme Court will adopt the analysis of East River.
E.
We recognize that our conclusion may not be considered congruent with two recent cases in the Pennsylvania intermediate appellate court. In
Industrial Uniform Rental Co. v. International Harvester Co.,
We restate that our role in this case is predictive.
Wilson v. Asten-Hill Manufacturing Co.,
F.
In our present analysis, a murky trudge through sophisticated nuances gives way to an unencumbered flight to basics. Damage to a product means simply that the customer has received “insufficient product value,”
East River,
— U.S. at-,
We are uncomfortable that the decision we reach today conflicts directly — on a similar fact pattern — with our holding in
Pennsylvania Glass Sand
in predicting how Pennsylvania courts will resolve this problem. But in the interim the Supreme Court has spoken; its words are loud and clear.
See
Internal Operating Procedures of the United States Court of Appeals for the Third Circuit, Chapter 8C, at 25;
United States v. Babich,
VI.
We have determined that Aloe did not present sufficient evidence of causation to submit its negligence claim to the jury. 2 We have also made a studied conclusion, or perhaps more accurately an educated guess, that Pennsylvania will declare as state law that which the United States Supreme Court has since formulated as federal law. For this reason, we will reverse the district court’s denial of Clark’s motion for judgment notwithstanding the verdict. We will remand this case to the district court with a direction that it enter judgment in favor of Clark. 3
Notes
. The district court entertained Aloe’s motion for delay damages prior to the Pennsylvania Supreme Court’s decision in
Craig v. Magee Memorial Rehabilitation Center,
. Judge Seitz joins in the judgment of the court solely on the basis of the court’s conclusion with respect to causation.
. In light of our holding on the damages issue, we need not address Clark’s additional contentions on appeal.
